This is a good episode, even if not original. It's a Faustian tragedy.
Kristin starts seeing her high-school boyfriend Eugene (the sexy Chad Willett), who's now a talented concert pianist and who has an unsettling agent, Leigh Noir (the creepy Stephen McHattie). Eugene had lost his edge until he met Leigh three years prior and Leigh had just killed Eugene's uncle. Eugene starts to get arrogant and Leigh doesn't like it at all.
Meanwhile, Derek gets suspicious of Eugene and Kristin resents it.
This is a very good episode. It manages to be entertaining and good drama. It has some rather creepy scenes, as Leigh can literally live through Eugene. The final scene between Eugene and Leigh is just brilliant.