Bad Blood

S2, E4: Nick discovers an ancient, terrifying evil is behind a series of grizzly murders plaguing the city, and he may not be able to stop it. He is unknowingly paired with Chief Inspector Liam O'Neal of Dublin C.I.D., a vampire hunter with a dark secret, who has tracked the murdering creature's bloody trail half way around the world. Wary of O'Neal, Nick begins an investigation of his own, learning the Chief Inspector's true identity, as well as that of the killer - Jack the Ripper. A vampire created by LaCroix, Nick had a chance to destroy the Ripper a century ago, but turned his back, unleashing a century of carnage around the world. He must now put aside his guilt and finish the job, but in doing so, O'Neal may finish him.