Legend (Part 1)

Legend Part 1 is the 'Pilot' episode of Season One of NCIS:Los Angeles.

Summary
When the body of a dead Marine is found in Arlington, VA, NCIS Special Agents Leroy Jethro Gibbs (Mark Harmon) and Timothy McGee (Sean Murray) travel to Los Angeles to work with the Office of Special Projects (OSP). NCIS believe that the Marine's death was related to an arms dealer named Liam, whom they discover to be a "legend" or false identity. Special Agent Callen (Chris O'Donnell) adopts the identity of Liam in an effort to catch the killer.