Continuity mistake: "Treasure of the Ages": In the beginning, one diver stabs the other, releasing a cloud of blood into the water. In the very next shot, however, not a trace of the blood remains. It couldn't possibly dissipate in that short a time. (00:02:30)
Continuity mistake: "Happy Valley": Just before the station wagon crashes and burns, it collides with a red car parked on the street. The shot cuts to an opposite angle from the neighbors' point of view, and the red car disappears. (00:04:00)
Continuity mistake: "A Stranger in Time, Part 2": Darien crawls through a sewer pipe and exits through a rusty grate, yet doesn't have a speck of dirt on his clothes. Later in interrogation, smudges appear on his sweatshirt, but those vanish again when he escapes. (00:26:45)
Continuity mistake: "Cool Hand Darien": When Luther breaks the chain on his shackles, he is still wearing the leg cuffs and the trailing pieces of chain on either side. He doesn't stop anywhere to come across a key, but when he bursts into the mine to rescue Darien, the shackles have disappeared. (00:35:00)
Continuity mistake: "Out for Blood": Parker disintegrates a crystal decanter and wine glasses with his laser weapon, then fires at several more things in the house. During this sequence, he zaps the same decanter and glasses, which seem to have re-integrated, over again. (00:37:15)
Continuity mistake: "Lethal Weapons": Darien is holding a disintegrator rifle when he leaps over the electronic fence. It flies from his hands when he lands, skidding across the porch, but disappears from the background when he gets up. It reappears just in time for him to snatch it up and shoot Cole with it. (00:39:10)
Continuity mistake: "A Stranger in Time, Part 2": Darien's arrival in 1993, shown in part 1, is recapped in part 2. But the director appears to have chosen different takes for the recap. Much of the dialogue differs substantially, and Selma's explanation that he's materialized in the ladies' room is left out altogether.
Continuity mistake: At least three different birth years are given for Darien Lambert in various episodes, among them 2163, 2160, and 2157.