A tattooed NCIS agent with a black belt goes undercover to find the killer of a Navy petty officer -- can he get what he needs without getting caught?

After a young mother, the girlfriend of a Navy sailor, vanishes, NCIS agents face a difficult investigation into one of their own that will challenge them on every level.

Agents open up about their emotions, fears, frustrations and successes in solving investigations that have national and international impact.

The investigation into the 2001 execution-style murders of a Navy sailor and her friend.

D'Wayne Swear, a former NCIS agent who inspired ``NCIS: New Orleans,'' takes viewers inside the real-life, cross-country search for the person who killed a young woman in San Diego.

The investigation into the 1996 deaths of two Navy petty officers stationed at the Oceana Naval Air Station.