At night at the Marine Corps Base, Quantico, Virginia, a hit-and-run driver strikes and kills a running woman Navy petty officer third-class; Gibbs and company investigate; Abby identifies the nature of the vehicle, Tony and McGee narrow the search to one pickup truck, and they find the owner, who stops talking, hires a mouthpiece, and in confidence tells her an incredible alibi. Abby confirms that someone else drove the truck; the lawyer checks out the alibi and assures Gibbs that it's solid, but she properly declines to reveal the story; however, she drops a bread crumb, which Tony and McGee trace. Abby finds a thumbprint attached to a name, which leads the gang to a second Marine at Quantico. Tony and McGee develop a hypothesis about a three-way murder club; the weak link flips on his co-conspirators, so he gets the deal. Gibbs and the lawyer share a dinner and a pleasant conversation.