By James Hibberd
Updated May 24, 2011 at 07:51 PM EDT
Andrew Evans/PR Photos

Battlestar Galactica star Edward James Olmos has signed on to the sixth season of Showtime’s Dexter.

He’s going to play a “brilliant, charismatic professor of religious studies.” The former Admiral Adama is added to a cast list that includes previously announced guest stars like Colin Hanks and Mos (formerly Mos Def). Production on the next season starts on May 25 and the show debuts this fall.

Here’s a teaser (no new footage, though):