The actor will appear in Episode 5.09: Everybody Wants to Rule the World, playing Jackson Herveaux, the father of Joe Manganiello's Alcide. We first meet Jackson during a flashback scene from the 1980s when Alcide and his girlfriend, Debbie Pelt, were teenagers. It is said that Jackson was, "powerful, inspiring, and heroic" back in the 80s, but now he has given up on life.
Jackson will be a recurring guest star, although it isn't known how often he will pop up this season. As of now, Episode 5.09: Everybody Wants to Rule the World will likely air on Sunday, August 5.
Robert Patrick will also be seen in the new ABC series Last Resort that will air on Thursday nights at 8 PM ET. A series premiere date has not been announced yet.