The Devil You Know - S1.E11

The head of security at a bank is first drugged and framed as an alcoholic, then killed later by a telephone repairman. An Immortal, Victor Hanson, is responsible for both: he plans to steal the Valentino Diamond and needed the security plans. Victor is also making a play for Amanda, hoping to get her to help him steal the diamond before he kills her. The security guy is Nick's old mentor, and he soon spots Victor despite his disguises and realizes he is the same guy who is dating Amanda. Amanda initially refuses to believe Nick's accusations, thinking he's jealous. However, Victor tries to blow up Nick and Lucy lets Amanda knows about it. Rather than go ahead with the robbery, she fights Victor but Nick breaks in. He shoots Victor and then engages in pursuit. He's about ready to cut off Victor's head with a knife when Captain Magnus, another friend of the security guy, shoots Victor and he falls into the water. The body isn't found, and Nick and Amanda reconcile.