A mystery motif plays during a number of scenes throughout the series, frequently alongside the mystery theme.
- Desmond "forces" Locke to enter the Numbers and push the button. ("Adrift")
- Locke wakes Henry up after he is knocked out, and sends him through the vents to push the button. ("Lockdown")
- Locke watches Dr. Chang's message on the Flame computer. ("Enter 77")
- Captain Gault shows Sayid and Desmond the black box from the fake Oceanic 815. ("Ji Yeon")
- Dr. Chang walks through the Orchid work site. ("Because You Left")
- Sawyer questions Daniel on his knowledge of time travel.
- Miles agrees to take the corpse out to Dr. Chang at the Orchid work site. ("Some Like It Hoth")
- Daniel watches Dr. Chang as he inspects the Orchid site. ("The Variable")
- Daniel explains his plan to detonate a hydrogen bomb.
- In a Previously on Lost recap, Daniel explains his plan to detonate a hydrogen bomb. ("The Incident, Parts 1 & 2")