The scene starts on a video game shooting game. Two boys are having trouble winning in the video game and said it was rigged for players to lose; however, on the other side someone was getting the high score killing all opponents -- a marine. The two boys were in awe and the next scene shows the marine talking to the boys encouraging them to enlist in the marine service. He was boasting about travel and they'd have no need to worry about combat because as he was explaining about the closest he came to a bullet was, then suddenly he was shot with what looks like a sniper bullet -- one shot, one kill.
The shot at marine is a recruiter for the marines and a number of recruited marines are mad at him since they have not received the kind of life told to them by the marine. They went after marines he recruited and were snipers as Abby confirmed the shot was made by a very good sniper -- 600 metres at an angle.
While they were interviewing the suspect another recruiter marine was shot by a sniper. When NCIS came to the scene the FBI arrived because it happened near the Maryland area, FBI territory. Gibbs and the FBI had a pissing match and NCIS managed to sneak and get the bullet without the FBI knowing. They did not need the body because it was obvious the sniper bullet killed the marine.
The NCIS feels the killer is one of those turned down by the marines during recruitment who wants to prove themselves. Before he kills again in the next 24 hours Gibbs volunteers to be a recruiter to set up a trap to the killer. Kate becomes the assistant of Gibbs who dresses up like a marine while Tony was excited except that he got the job of an electrician. Kate was profiling everyone that went in the room and thought it was one of the guys when Gibbs saw the feather in the water refill, something that was left in all the recruitment office where the recruiter were killed. They figured out it was the water delivery man. Gibbs was looking at the window when the sniper shot but NCIS already secured the area with a bullet proof glass. They came and closed in at the shooter.