S2, E17: Determined to find the reasons behind a fellow officer's suicide, Nick Knight ignores his orders from Internal Affairs to stay away from the investigation and instead, focuses on a member of the Internal Affairs team. Meanwhile, in his never-ending quest to regain his mortality, Nick becomes a guinea pig for another of Natalie's supposed cures. As always, the cure is promising at first but complications soon develop. This time Nick is oblivious to his apparent addiction to the drug and the consequences of his drug induced behavior.