Ziva's undercover assignment which consists of her trailing a serial killer suspected of having killed five women while cutting off their fingers and preserving them as trophies goes horribly wrong when the man she's tracking becomes suspicious of her, forcing Ziva into a life or death situation. As Ziva tries to come to terms with what she's done, the team soon realize that Hoffman might have a partner which leads them to search for the supposed copycat killer.