About NCIS Season 1, Episode 21 : Split Decision

When a Marine is killed with a specialized military weapon, the agents investigate the illegal weapons market and find an undercover ATF agent (Bellamy Young) also working on the case, and Gibbs asks her to work with them to find the killer. Guest Stars: Sean Murray, Brian Dietzen, Bellamy Young, Scott MacDonald, Laz Alonso, Samuel Witwer, Erin Wiley Sands, Michael Graziadei, Adam Hendershott, Stuart Stone, Laurence Cohen, Kevin Sizemore,