On the freighter
Days 96-99 (Season 4)
Captain Gault in ("Ji Yeon").
Gault ordered Omar and Keamy to fetch Frank Lapidus from the sickbay so that he could talk to the pilot. When they arrived, Sayid, who was being held in sickbay, requested to talk to the captain as well, but Omar discounted Sayid's request. ("The Constant")
After Regina committed suicide, Gault ordered the crew to refrain from trying to rescue her. He informed Sayid and Desmond that the engines of the boat had been sabotaged, that his orders, from Charles Widmore, the freighter's owner, were to move the freighter to "safer waters" away from the Island once the engines had been repaired. Gault showed the two the flight data recorder ("black box") recovered from the purported wreckage of Oceanic Flight 815. The ship's physician Ray volunteered his opinion of the captain to Sayid: the Captain "tells it like it is," but the two had "better not cross him." ("Ji Yeon")
That night, Gault discovered two crewmembers attempting to escape the freighter in the ship's tender. He beat the would-be deserters with his fists, telling the other crewmembers that he was doing so to save their lives, reminding them of the fates of George Minkowski and Brandon, who had earlier made an ill-fated voyage in the ship's tender and died of the effects of temporal displacement.
Later, Sayid and Desmond burst into Gault's room with Michael, and Sayid reveals that Michael is the saboteur and that his name is not Kevin Johnson. Gault stares at them and does not answer. ("Meet Kevin Johnson")
Keamy takes Gault's key by force in ("Cabin Fever").
Keamy immediately accused Gault of ratting him out to Benjamin Linus, because Ben knew Keamy's history. Gault denied this, taking Keamy to Michael. Keamy attempted to kill Michael once discovering he was the rat, even though Gault tried to stop him. However, the handgun would not fire and Michael was spared. Gault then revealed to Keamy that Michael was needed to fix the engines, since Michael broke them. Keamy then confronted Gault for his key, which Gault refused to give up, stating that Keamy was suffering from the same sickness that afflicted Regina. However, Keamy forcefully took Gault's key, which was used with Keamy's key to unlock a safe with a secondary protocol book in it. Keamy gave Gault his handgun and told him to fix it.
Gault holds Keamy at gunpoint on the deck of the Kahana in ("Cabin Fever").
Gault was shocked when Keamy threatened to torch the island, and was ordered by Keamy to fix his gun. Gault then found Sayid and Desmond on the deck, and instructed them to hide from Keamy. However, Sayid counterproposed, and asked for the Zodiac raft of the Freighter. Gault agreed, and Sayid set off on the boat. That night, as Keamy prepared to leave, Lapidus was having second thoughts about flying the mercenaries to the island after talking to Michael. After watching Keamy slit Ray's throat, Gault confronted him, firing a warning shot with the now operational handgun and telling him to stand down. Keamy then revealed a device strapped to his arm. Gault asked what the device was, but was suddenly shot dead by Keamy, who had quickly unholstered another one of the mercenaries handguns. Keamy retrieved his handgun from Gault and took off on the helicopter. ("Cabin Fever")
- "Captain Gault" is a fictional sea captain created by English writer William Hope Hodgson. A captain for hire, Gault is a morally ambiguous and mysterious character. A collection of his stories can be found in the book Captain Gault, Being the Exceedingly Private Log of a Sea-Captain, published in 1917.
- In Ayn Rand's novel, Atlas Shrugged, John Galt is an engineer and entrepreneur who organizes a strike of the world's captains of industry. Galt invites them all to a location that is shielded by a "ray screen," so that those in the outside world cannot find him. Grant Bowler, who portrays Gault, plays the male lead in the Atlas Shrugged film adaptation.
- During casting, the character of Gault was known as "Huston, 50s, male, Caucasian, weathered face, salt and pepper hair, a man who immediately commands great authority but someone you don't want to cross. He has a job to do and he doesn't allow anything to get in his way - even the death of his employees..." 
- Out all of the main characters. Gault has only met Michael, Frank, Desmond and Sayid.