Ziva visits Gibbs in his basement; she hands him a gift and asks to rejoin the team; he tells her to see Vance. Three young men die under bizarre ritualistic circumstances during what they called a bachelor party; one was a Marine staff sergeant; Gibbs and company investigate. Ducky says that all three victims, when they died, were semiconscious, drugged by spiked champagne; Tony learns that the party was not a bachelor party at all. Abby gives a private lecture and welcome to Ziva, who passes her first psych screening. Gibbs and McGee separately find a connection and more between the victims and a Baltimore cop, who arranges to meet Tony, but the cop dies first. Ziva passes her second psych evaluation. The gang find the rest of the pieces and put them together, and they bust the bad person. Ziva approaches Gibbs again in his basement, and she says that they need to talk. Later Tony and McGee find Ziva at her desk, setting a plant in place.