According to The Hollywood Reporter, Sebastian Roche has joined Fox's Fringe as a recurring character. His is going to play a new villain on the sci-fi based series.
Fox isn't saying much about the character but he "is a soldier from another dimension who is not quite human/not quite machine, trying to gather information for opening a stable door to the other side."
Roche is going to replace Thomas Kretschmann, who was initially cast in the role and was last seen in the October 8 episode. His current workload would not allow him to be a recurring character on the show.