- This article is about the episode. For the fixed value, see Constant. For the orchestral piece, see "The Constant" (composition).
"The Constant" is the fifth episode of Season 4 of Lost, and the seventy-seventh produced hour of the series as a whole. It was originally broadcast on February 28, 2008. The helicopter hits turbulence on its way to the freighter, and Desmond experiences unexpected side effects; as his consciousness travels in time he and a key character discover their "constants." The episode follows Desmond's consciousness in a continuous narrative.
2004 – Helicopter
Desmond panicking in the helicopter
Desmond and Sayid travel on the helicopter to the freighter piloted by Frank. Desmond is looking at the picture of him and Penny. Frank is flying the route that Daniel gave him, and Sayid worries when their course leads straight into a thunderhead. They experience turbulence which becomes progressively worse and Frank struggles to keep to the correct bearing. The helicopter drifts from the 305 heading to a heading of 310 and Desmond begins experiencing flashes. ♪
1996 – Royal Scots Regiment
Desmond wakes up in a military barrack.
Desmond wakes in the Royal Scottish Regiment military barrack at Camp Millar (north of Glasgow, Scotland) as morning drill begins. The Sergeant-Major starts to shout at him because he did not respond promptly to the wake-up call. He demands an explanation and Desmond explains he was having a very vivid dream about being "in a helicopter, Sir,...and there was a storm, Sir, and...I...don't remember the rest, Sir." The Sergeant-Major comments that it was at least a military dream, but still mocks him. As punishment for Desmond's lack of concentration the Sergeant-Major orders the entire platoon to get ready for the morning routine in double time, four minutes instead of the normal eight minutes.
2004 – Helicopter/Freighter
Keamy talks to Desmond.
Desmond wakes up in present time after his flash and is very disoriented. He struggles with his seatbelt and is panicking, appearing as if he wants to jump out of the helicopter. Sayid tries to calm him down, asking him if everything is okay. Desmond, puzzled and afraid, asks Sayid what his name is, not recognizing him.
Back on the beach, Jack and Juliet are worrying about the helicopter, as they haven't heard from Desmond or Sayid for a day. They question Charlotte and Daniel as to why there is no news of their friends. Charlotte is indifferent even though, as Juliet points out, the freighter is only 40 miles away which is about 20 minutes of flying. Juliet's main concern is that neither Charlotte or Daniel seem at all concerned. Against Charlotte's wishes, Daniel admits that the perception of time on the Island might be different than the time experienced off the Island. He says that as long Frank uses the bearings that were given to him, the people on the helicopter should be fine. If not, there could be "side-effects."
Desmond then pulls out of his pocket the picture of him and Penny, which appears to relax him. ♪ The thunderstorm clears, and the helicopter lands on the freighter. Keamy and Omar come running toward Frank, asking who Desmond and Sayid are and why he brought them with him. Frank explains that they are survivors from Flight 815. ♪ Keamy, in charge, says that he shouldn't have brought them on board. Desmond is distressed and starts yelling that he doesn't know Sayid and Frank. Sayid agrees to let Keamy and Omar take Desmond to the doctor, but Desmond has another flash before they can.
1996 – Royal Scots Regiment
Desmond stands in the yard while the rest of his platoon do crunches.
Desmond is in the rain, standing while all the others in his platoon do crunches. The Sergeant-Major ridicules him again and makes the entire platoon run as a punishment for Desmond's erratic behavior. Afterward, Desmond speaks to one of his friends in the platoon, and tells him about the "dreams" he has been experiencing. His friend is in disbelief and asks if there was anyone he knew in the "dream". Desmond remembers that in the helicopter he was holding a photo of Penny. He hurries to a nearby phone booth to call her. However, just as he is about to go in, someone bumps into him, sarcastically thanking him for the extra work the Sergeant-Major made them do on the account of Desmond's disobedience. As Desmond reaches down to pick up the dropped coins, his consciousness returns to the freighter.
2004 – Freighter
Sayid and Frank do a crucial deal on the freighter's deck.
Keamy and Omar introduce themselves and bring Desmond down to the sick bay, only to lock him in. Desmond panics and starts pounding on the door and screams to be let out. He hears a voice behind him saying "You have it, too." Turning, he sees a man lying on a bed, strapped to it. The man asks him if "it is happening" to Desmond as well.
Ray gives Minkowski drugs to calm him.
Meanwhile, on the upper deck, Sayid surveys the freighter. He notices a closed-circuit camera on the railing beside him. Looking up to a higher deck, he sees Keamy and Frank arguing. As Frank comes down the stairs to meet with Sayid, Sayid asks him why they left at dusk but arrived in midday. Frank doesn't know. Sayid asks for the phone, which Frank will give him only if Sayid gives him the gun. Sayid gives Frank the gun and calls Jack. He tells Jack that Desmond doesn't seem to remember anything; Jack puts the phone on speaker. Daniel asks if Desmond has been subjected to an intense dose of radiation or electromagnetic energy. He then says that by coming out of the Island, some people "might get a little confused," but it is not amnesia.
In the medical room, after Minkowski falls asleep, a doctor, Ray, enters. Minkowski wakes up and tells Ray that "this" will happen to everyone else once they go back to the Island. The doctor injects Minkowski with a sedative. The doctor then examines Desmond's eyes with a light, so he can "help him." In the middle of a phrase, Desmond has another flash.
1996 – Royal Scots Regiment
Desmond calls Penny in the military base.
After picking up the coins on the ground, Desmond enters the phone booth to call Penny. Troubled by his call, Penny tells him that he shouldn't be calling her as he broke off with her and then joined the army. She adds that she has moved, and hangs up after telling him to not call her anymore. When Desmond tries to respond, the flash ends.
2004 – Freighter
Faraday talks to Desmond, while going over his notes.
Sayid and Frank come down to the medical bay to bring Desmond the satellite phone, but Ray pushes the alarm button. Sayid quickly gives the phone to Desmond, because Daniel, who is on the other end, urgently needs to speak with him. Daniel asks Desmond "what year" he thinks he is in. Desmond answers that it is 1996 (eight years ago). Daniel then asks him where he is "supposed to be." When Desmond tells Daniel that he is supposed to be on the base, Daniel tells him to catch a train to Oxford to meet with his past self and gives Desmond some mechanical settings to relay, along with an extra phrase that Daniel assures him will convince him that the story is legitimate. When Omar and Keamy force their way in to the medical bay to stop the call, Desmond has another flash.
1996 – Oxford University
Daniel and Desmond watch the rat experiment.
Desmond visits Daniel at Oxford. The 1996 Faraday chastises a student and rants to himself. Desmond approaches and tells Daniel that he has been to the future where Daniel told him to find him in the past. Daniel is suspicious, feeling that his colleagues are playing a prank on him. Desmond recites the settings Daniel gave him: 2.342 and 11 Hz. Faraday's interest is piqued, but not sufficiently. Desmond then uses the final piece of information Daniel had given him on the phone: "I know about Eloise."
Desmond goes with Daniel to a secret room, where Daniel does what "Oxford frowns upon." Daniel then asks Desmond if his future-self remembers this particular meeting between the two men, to which Desmond responds negatively. Desmond adds that "maybe you just forgot," which makes Daniel laugh. Daniel adds that one cannot change the future, as he puts on an anti-radiation vest. Desmond asks why he doesn't get one, but Daniel says that it is necessary only for prolonged exposure (as he does this kind of thing 20 times a day). Desmond asks why Daniel doesn't put something on his head, but Daniel again laughs at the comment. Daniel pulls out Eloise the rat from a cage and puts it in a maze. After calibrating a machine according to Desmond's instructions, Daniel turns it on to "unstick Eloise in time". The machine emits a bright purple ray on the rat and then stops. Quickly, Daniel takes off his anti-radiation vest and looks at the rat without doing anything yet, as "she is not back yet". When she is, Daniel removes the little door at the beginning of the maze to let the rat walk in it and find the exit. Without any hesitation, the rat quickly finds the exit of the complex maze. ♪ Daniel is extremely happy, but Desmond doesn't understand why this is incredible. Daniel answers that he built the maze the morning before, and he is not going to teach the rat how to run it until an hour later: he has sent her consciousness, her mind, in the future. Desmond then confronts Daniel as to why he sent him here if not to help him. He then adds that Daniel in the future is on an Island, to which Daniel replies: "Why would I go to an Island?" ♪
2004 – Freighter
Desmond tries to "get back".
Back in the bay, Keamy takes the phone from Desmond. He and Omar take Frank outside the room, because the captain wants to talk to him. Sayid adds that he too wants to talk to the captain, to whom Keamy answers sarcastically: "I'll be sure to let him know. In the meantime have a seat." ♪ Desmond tries to "get back" using the doctor's flashlight, but doesn't succeed. After Sayid calls Desmond by name, Minkowski suddenly reacts. He tells them that he is George Minkowski, the communication officer. Before they strapped him down to a bed all the calls to and from the boat went through him in the radio room. Every so often, a light flashed on his console, to indicate an incoming call. They were under strict orders never to answer these calls, which were from Desmond's girlfriend: Penelope Widmore.
1996 – Oxford University
Faraday explains the importance of a constant to Desmond.
Desmond wakes up in Daniel's Oxford room. Desmond replies to Daniel that he was in the "future" for about five minutes. Daniel seems somewhat astonished that Desmond was "gone" for nearly 75 minutes and tells him that the more time he goes back and forth, the harder it gets, as in his case the progression is exponential. Desmond then notices that the rat is dead, from a brain aneurysm. Desmond confronts Daniel about it, but Daniel says that he doesn't know if Desmond is going to die also. Eloise's brain short-circuited, she couldn't tell the difference between the past, the present or the future, as she didn't have anything to attach herself to: she did not have a constant. Daniel tells him about the need for Desmond to have a constant, something that is present in both times and that he sincerely cares about and can recognize. ♪ Desmond grabs the phone and calls his constant, Penny, but the number has been disconnected.
2004 – Freighter
Sayid and Desmond release Minkowski from his bed.
When Desmond's consciousness returns to 2004, he knows he has to contact Penny. He tells Sayid, but Minkowski interrupts them to say that two days earlier, someone sabotaged all the equipment. All communication with the mainland has been lost. Minkowski could have fixed it, but he's "unstable." Sayid asks where the radio room is and frees Minkowski to show them the way. Sayid asks how they are going to get out of the room, but Minkowski notices that the door is open: they seem to have "a friend on this boat," as Minkowski says. Desmond notices that George has started to bleed from his nose as they prepare to leave.
1996 – Auction
Charles Widmore at the auction
Charles Widmore is bidder #755 at a Southfield's auction for lot #2342, the journal of the Black Rock's first mate. The contents have not been published and are unknown to anyone outside the family of the seller, Tovard Hanso. Charles wins the auction for £380,000. Meanwhile, Desmond arrives and tries to get past the guard to talk to Widmore. After the auction ends, Widmore walks out and agrees to talk to Desmond. In the men's bathroom, Desmond says that he needs to get in touch with Penny immediately. He doesn't know how to reach her as her number has been disconnected. After Widmore talks about Desmond's cowardice and his "second thoughts", he ultimately gives him her address written on a card so that she can tell him herself that she hates him. As Widmore leaves the bathroom, he leaves the faucet on. Just as Desmond is about turn off the faucet, the flash ends. ♪
2004 – Freighter
Minkowski dies, after not being able to find a constant.
On the boat, Sayid, Minkowski, and Desmond are going to the sabotaged radio room. Minkowski says that "it" is happening faster and is getting harder. Desmond then asks George how it happened to him. Minkowski tells him that they were bored out of their minds, waiting for their orders, anchored "here," so he and Brandon, another crew member, decided to take the ship's tender to see the Island. But Brandon started acting erratic so they turned around. Soon after, Brandon died and Minkowski grew unstable. Sayid looks at the destroyed equipment and asks Minkowski who is responsible for the damage. George doesn't seem to know and adds that he feels sorry for the person when the captain finds out. He suddenly phases out again. Sayid uses his military expertise to repair the phone. Desmond notices a calendar that says the year is 2004. Sayid sees it also and notes that it's almost Christmas. As Desmond realizes the date he starts to bleed from his nose, and suddenly Minkowski has a fit and bleeds again. Minkowski's final 'trip' cost him his life, as he returned to 2004 he dies, his last words are I can't get back.
1996 – Penny's flat
Penny gets the Christmas Eve call 8 years later.
Desmond wakes in the bathroom, the sink overflowing with water. After refreshing his face, he goes to see Penny. She opens the door to a distraught Desmond and says she wants to have a "clean break" from Desmond, but he insists she listen to him, pleading for her phone number. After entering the flat, he tells her that he needs her phone number so he can call her in eight years (December 24, 2004). Ultimately even though she doesn't understand why he just can't call her tomorrow and after promising to leave if she gives him the number, she gives him Desmond her number: 7946 0893. She pushes him out the door while he pleads that she not change the number.
2004 – Freighter
"If anything goes wrong, Desmond Hume will be my constant"
Desmond comes back and tells Sayid the London phone number. Sayid repairs the phone, dials it, and passes it to Desmond. Desmond engages in a joyous and tearful call with Penny where she tells him she has been looking for him for three years, also confirming to Desmond her conversation with Charlie from the Looking Glass. Penelope is wearing a ring on the ring finger of her right hand. She knows about the Island, has researched it, and is desperately trying to find him. They each say they love the other as the phone battery dies out. Desmond then thanks Sayid by name, now with his memory back. He is, he says, "perfect." ♪
- Damon Lindelof and Carlton Cuse call this "arguably" their favorite episode of Lost. It is also many viewers' favorite.
- This is the first episode that doesn't use flashbacks or flashforwards. We experience Desmond's flashes as he does—chronologically through both time periods.
- This episode featured several elements which were clues from the alternate reality game Find 815:
- Penny's phone number is 7946 0893 in London. "020 7946 0893" was a Season 4 bonus clue in Find 815. (Find 815 clues/January 9)
- The 020 region code was not introduced until 22nd April 2000. Before this London had a code for Outer London (0181) and Central London (0171), and the local number had 7 digits, not 8. All 0171 numbers were converted to 020 7 on this date. So Penny's number would have originally been 0171 946 0893.
- Although this looks like a UK telephone number in London, it is an unassigned number (Ofcom specifies that numbers beginning with 020 7946 0 are for drama purposes ).
- Penny's address is 423 Cheyne Walk in London. "423 Cheyne Walk" was a Season 4 bonus clue in Find 815. (Find 815 clues/January 9)
- It is near where Desmond's photograph with Penny was taken. In addition, Widmore Industries has its offices in the same neighborhood. ("Flashes Before Your Eyes").
- Cheyne Walk is a famous street in London known for its famous inhabitants. Residents have included Mick Jagger, Keith Richards, George Eliot, Dante Rossetti, and Henry James (who wrote The Turn of the Screw).
- "Queen's College, Department of Physics" and "Southfields" were Season 4 bonus clues in Find 815. (Find 815 clues/January 30)
- "Camp Millar" was a season 4 bonus clue in Find 815. (Find 815 clues/January 23)
- Penny's phone number is 7946 0893 in London. "020 7946 0893" was a Season 4 bonus clue in Find 815. (Find 815 clues/January 9)
The calendar on the wall.
- The ledger that Charles Widmore buys in the auction is the same as the journal referenced by Oscar Talbot in Chapter 5 of Find 815. Talbot was working for a branch of the Widmore Corporation, and says that his employers had the journal.
- According to the calendar on the wall, as well as Desmond, the real-time events of this episode take place on Day 94 (Christmas Eve), two days after Sayid, Desmond and Frank left the Island.
- Southfield's, the organization holding the auction, is an anagram for "shifted soul." This might have been done to reflect the way that Desmond's mind, or soul, was shifted through time. (Anagrams)
- The information about Faraday's device is an example of the Bootstrap Paradox. It is given to Desmond by Faraday himself, who is only aware of it because Desmond told him in the past; thus, the information was never actually discovered. Another example of this would be Richard's compass.
- This episode is rated TV-PG-LV.
- This episode features only two main characters from Season 1, Jack and Sayid, the fewest of any episode until "Jughead". Also, this episode features only six main characters, tying with "The Man from Tallahassee", and falling behind "A Tale of Two Cities", "Not in Portland", and "Stranger in a Strange Land" (each of which feature only the same five) and "Dead Is Dead", which has only four.
- A podcast rehash for the episode was released on February 28, 2008. (Official Lost Podcast/February 28, 2008)
- The scenes in the military camp were filmed on the slopes of Diamond Head crater. 
- The dog seen at Oxford university when Desmond finds Faraday is the same dog used for the painting in Jacob's cabin. This is Lulu, who was the pet of episode director Jack Bender at the time (she now belongs to costume designer Roland Sanchez).
- The phone that Sayid connects to the battery is a standard Lineman's Handset (looks like a Harris TS22).
- The demolished audio mixer prop () that Sayid takes out of the rack to look at is actually a RadioShack SSM-1850 home mixer (). Klerk-Technik graphic equalizer and Tascam DAT machine are also seen in the same picture.
- This episode was nominated for (but did not win) the 2009 Hugo Award for Best Dramatic Presentation, Short Form. This was the first time a Lost episode had been nominated for this prestigious fan-voted science fiction award since "Pilot, Part 1" and "Pilot, Part 2" were nominated in 2005.
- An audio commentary by Mark Goldman, Damon Lindelof, and Carlton Cuse for this episode is available on the Season 4 DVD.
- According to the audio commentary on the Season 4 DVD, the final scene was to involve Charlotte approaching Daniel with the bag containing the gas masks, directly setting up the events of the next episode. Due to the dramatic and emotional impact of the scenes preceding it, however, they decided that Daniel reading about Desmond in his journal was enough of a cliffhanger to end the episode.
- A Lost: On Location for this episode is available on the Season 4 DVD.
Bloopers and continuity errors
Parking fee collection machine outside Penny's townhouse.
- Outside Penny's house in 1996 Desmond passes a parking fee collection machine. The type features a solar panel on the top that powers it. These were not introduced nation-wide in the UK until 2002.
- On the blackboard in Daniel's office, Schrodinger's equation for the time evolution of a wave function is missing the Hamiltonian operator. The equation should read: , instead of .
- The helicopter is in flight to the freighter, but the RPM and oil pressure gauges, seen while viewing Daniel’s map taped to the instrument panel, both read zero which indicate the engine is turned off.
- This may be a result of the Helo being struck by lightning on the way to the island.
- The Queen's College, Oxford, does not have a physics department. Instead, the University of Oxford has various physics sub-departments situated throughout the city.
- Desmond repeatedly refers to the Sergeant-Major as "sir." Sergeant-Major is an enlisted rank, so the appellation of "sir" is inappropriate. It's possible that this is during basic training (when platoon sergeants use that title to get the recruits used to using it for officers), but a Sergeant-Major is the highest rank of enlisted personnel and would never be directly responsible for training a platoon of recruits.
The Season 4 soundtrack includes the following tracks from this episode:
|Animals • Black and white • Character connections • Children • Coincidence • Death • Deceptions and cons • Dreams • Economics • Electromagnetism • Eyes • Fate versus free will • Games • Good and bad people • Imprisonment • Isolation • Leadership • Life and death • Literary works • Mirrors • Missing body parts • Nicknames • The Numbers • Pairings • Parapsychology • Parent issues • Pregnancies • Psychology • Rain • Redemption • Relationships • Religion • Revenge • Salvation • Secrets|
- There are several references to the Numbers:
- Desmond's consciousness moves back and forth between 1996 and 2004 — 8 years apart. (The Numbers)
- Desmond's drill sergeant tells the recruits they have 4 minutes to "get in the yard" instead of the usual 8. (The Numbers)
- Penny lives at 423 Cheyne Walk (4-23 or 42-3). (The Numbers)
- The frequency that Faraday gives Desmond is 2.342 (23, 42). (The Numbers)
- The auction lot number of the Black Rock diary is 2342. (The Numbers)
- Faraday says that while Desmond was in a catatonic state in his room at Oxford, 75 minutes had passed. Desmond perceived the same amount of time as 5 minutes. The ratio of 75:5 is equivalent to 15:1. (The Numbers)
- The helicopter is marked with "N842M". (The Numbers)
- Both the adjustment numbers for Daniel's experiment and the Black Rock auction lot share the same number, 2342. (Coincidences)
- At the auction, Widmore is bidder number 755, the same numbers as the time ratio. (Coincidences)
- Charlotte earned her doctorate at Oxford. Daniel taught there. (Coincidences) (Character connections)
- Minkowski is unable to find a constant and dies as a result. On the other hand, Desmond is able to find a constant (Penelope) and apparently manages to avoid death. (Life and death)
- The doctor, Ray, examines Desmond's eyes. (Eyes)
- Daniel asks about Desmond being in contact with electromagnetism, a force that seems to affect people who come and go off of the Island. (Electromagnetism)
- Desmond and his military colleagues are exercising in the rain. It's also raining when Desmond calls Penny from the booth. (Rain)
- Daniel and Charlotte initially withhold from the survivors the effects of traveling to and from the Island. (Secrets)
- Desmond thinks he was having a dream at the regiment. (Dreams and visions)
- Eloise, central to the plot, is actually a rat. (Animals)
- Minkowski is strapped to a bed in the sick bay. (Imprisonment)
| Cultural references|
(direct references only)
|Art • Automobiles • Games • History • Literary works • Movies and TV • Music • Philosophy • Religion and ideologies • Science|
- Charles Dickens: After the auctioning of the Black Rock ledger, some of Charles Dickens' belongings are placed up for bidding. Desmond himself has a deep relationship with Dickens' novels since the telling Our Mutual Friend is supposed to be the last novel he wants to read before he dies. (Literary works)
- Hawaiian language: As the helicopter approached the freighter, a sign near the landing pad indicated the name of the ship: Kahana. Kahana means the drawing of a line, cutting or turning point in the Hawaiian language. [source: Pukui & Elbert, Hawaiian Dictionary] (Science)
- Relativity: The majority of the notes on Daniel's chalkboard and notebook are (introductory) notes on Special Relativity and General Relativity, with a small amount of quantum mechanics scattered in. (Science)
- Special Relativity deals with linear contractions/dilations of space and time.
- General Relativity deals with the curvature of space and time.
- There have been evidences of both Special and General Relativity on the island - as Faraday pointed out (and his payload experiment showed), there is a contraction of time when you go to or leave the island.
- Faraday constant: Faraday wrote in his journal, "If anything goes wrong, Desmond Hume will be my constant." In physics and chemistry, the Faraday constant is the amount of electric charge per mole of electrons. The Faraday constant was named after British scientist Michael Faraday, and is widely used in calculations in electrochemistry. (Science)
- All Good Things...: The series finale of Star Trek: The Next Generation features Captain Picard in three different timelines. He becomes "unstuck" in time, like Desmond and Billy Pilgrim. Also, Desmond's trip to contact Daniel at Oxford is reminiscent of Picard's trip to visit Data at Cambridge. In the Season 4 DVD commentary Damon Lindelof confirmed that "All Good Things" was a big influence in writing "The Constant" episode, while Mark Goldman states that he took inspiration from the Star Trek episode's editing style in deciding how to piece together Desmond's time jumps. (Movies and TV)
- The Waste Lands: is the third book in Stephen King's, Dark Tower Series. The key used in this book is very similar to The Constant - an anchor existing in both realities that can cure madness caused by time travel. (Literary works)
- Slaughterhouse Five: Desmond confides his vivid dreams to his military friend Billy. Billy Pilgrim is the main character in Slaughterhouse Five, the second chapter of which begins with the narration, "Listen: Billy Pilgrim has come unstuck in time."; Daniel says he will unstick Eloise in time. (Literary works)
- Flowers For Algernon: In the short story, the death of the eponymous lab mouse foreshadows the possible death of Charlie, who was undergoing the same experiment.
- VALIS: The pink beam of light that lets Eloise the rat travel through time is a reference to a similar pink beam of light, believed by the main character to be a transmission from an alien satellite, that is featured in this book, which is shown in the episodes surrounding "the Constant." (Literary works)
|Comparative: Irony • Juxtaposition • Foreshadowing Plotting: Cliffhanger • Plot twist Stock characters: Archetype • Redshirt • Unseen character|
Story: Flashbacks • Flash-forwards • Flash sideways • Framing device • Regularly spoken phrases • Symbolism • Unreliable narrator
- This episode is the first to contain neither a flashback nor flashforward. Instead, Desmond's consciousness from 1996 is traveling between 1996 and 2004 within the context of the present time narrative.
- The Desmond-centric episode "Flashes Before Your Eyes" also has Desmond "time travel", but only in the context of a flashback that spans almost the entire episode.
- Minkowski says he can't get back. (Regularly spoken phrases)
- In 1996 Daniel wonders if his future self knows about his meeting with Desmond, to which Desmond says Daniel probably forgot. Daniel replies sarcastically, "Yeah, how would that happen?" Daniel would later suffer from some form of memory loss. (Foreshadowing) (Irony)
- In 1996 after Daniel covers his chest to protect himself against the radiation of his ray and explains to Desmond that he (Daniel) needs it because he is constantly exposed to it, he seems surprised when Desmond points that he should be covering his head as well. However, he just shrugs it off and proceeds with the experiment. This is probably foreshadowing the cause of Daniel's chronic loss of memory as seen in the future. (Foreshadowing)
- Minkowski says "We anchored here" about the freighter just while Desmond is trying to anchor himself during his time-traveling experiences. (Juxtaposition)
- The episode ends with Daniel reading in his journal "If anything goes wrong, Desmond Hume will be my constant." (Plot twist) (Cliffhanger)
|A-Missions • Crimes • Economics • Leadership • O-Missions • Relationships • F-Missions • Rivalries • S-Missions|
- Desmond's love for Penny anchors him in time. (Relationships)
- Sayid trades his gun for communication. (Economics)
- Desmond and Sayid land on the freighter to investigate it. (A-Missions)
- Daniel helps Desmond find his constant. (F-Missions)
- Penny tells Desmond she realized he was alive and on an island when she spoke to Charlie. ("Through the Looking Glass, Part 2")
- Daniel refers to meeting Desmond before the helicopter took off. ("The Economist")
- Frank tries to fly the helicopter on the bearing Daniel gave him. ("The Economist")
The comm panel ("The Constant")/("Through the Looking Glass, Part 2")
- Sayid is asked to perform urgent electronic repairs under mysterious circumstances, and calmly does so without demanding a full explanation. ("Orientation")
- Daniel has a rat in a maze, with cheese. John Locke described the survivors pushing the button in the Swan as "rats in a maze, with no cheese". ("?")
- Daniel asks if Desmond had recently been exposed to high levels of radiation or electromagnetism. ("Live Together, Die Alone, Part 2")
- Frank is told by Daniel to follow a bearing of 305, which is a Northwest direction. Eko's stick bore the inscription "Lift up your eyes and look north - John 3:05", which Locke later followed as a bearing ("I Do")
- Ben told Michael and Walt to follow a bearing of 325 to find rescue. ("Live Together, Die Alone, Part 2")
- Ray puts a light in front of Desmond's eyes, which is also reminiscent of the title Desmond's previous time-travel episode. ("Flashes Before Your Eyes")
- In the radio room, there is the same communications panel that we can see in the Looking Glass communication room. ("Through the Looking Glass, Part 2") The only difference is a strange object on the right in the place of the orange LED. This machine seems to be in good condition in respect to the other in the same room.
- Desmond and Daniel have a conversation regarding Daniel's memory, which is shown to be affected in earlier episodes. ("Confirmed Dead") ("Eggtown")
- For fan theories about these unanswered questions, see: The Constant/Theories
- What is the nature of the time differential between the Island and the outside world?