NCIS: Season 1, Episode 20

1 - 20: Missing

The disappearance of a marine draws NCIS in to investigate, and it's discovered that several marines from the same unit have also vanished under similar circumstances. When skeletal remains of one of the missing men is found chained to a pipe in a small sewer room, Gibbs begins to suspect the unit CO (the only team member not dead or missing) as a serial killer. However, after Tony vanishes, the investigation takes on a more frantic pace and McGee is called in from Norfolk to help as Gibbs and Kate work against the clock to find Tony before it's too late.