The actor has signed onto play Dieter Braun, an ancient blood sucker who supplies intelligence to the Authority and relishes using torturous interrogation techniques. It is said the actor will have a recurring role this season, although it isn't known how many episodes he will appear in.
Production is currently under way on Season 5 of True Blood, which will premiere sometime this summer on HBO. Among other new casting additions this season are Christopher Meloni, Kelly Overton, Louis Herthum, and Dale Dickey.
Christopher Heyerdahl also recently starred on the AMC Western series Hell on Wheels as The Swede.