A cemetery grounds crew is shocked when they accidentally discover that a casket contains not one but two bodies. The extra passenger is revealed to be a Navy officer, Richard Coyne, who had been missing for 18 months.
Gibbs and McGee return to work with the proviso that they attend a mandatory psych eval with Dr. Confalone. Gibbs surprises everyone by immediately agreeing.
With Bishop acting as the boss, the team begins their investigations. They discover that Coyne had been slated to testify against a man named Leo Vairo, who was accused of stealing money from the safe of a gym. Coyne had intervened, saving the life of the gym owner, Pete.
Bishop and Torres are surprised to discover Coyne's wife has now begun a relationship with Pete, though they both claim the relationship began after Coyne's disappearance.
After Jimmy passes out in Autopsy, they learn that Coyne had been poisoned by powerful drugs as well as struck on the head.
They eventually discover that Pete had been importing powerful pharmaceuticals and that Vairo wanted to steal them, leading to the confrontation. Coyne's death was later revealed to be an accident, having collapsed and hit his head.
Dr. Confalone eventually signs off on both Gibbs and McGee returning to full duty. Gibbs decides to continue seeing her in a professional capacity.