Now this is a stroke of brilliant casting, especially after you read the character description and consider the possibilities for the 4th season of DEXTER! The Hollywood Reporter Live Feed blog just posted the news that actor John Lithgow has joined the cast for the upcoming season of DEXTER. Check this out...

Lithgow will play Walter Simmons, an unassuming, mild-mannered suburbanite who has been living a dual life as one of America’s most prolific and deadliest serial killers.  Dubbed the “Trinity Killer” because of his proclivity to kill in three’s, he relocates to Miami after being tracked by F.B.I. Special Agent Frank Lundy (Keith Carradine).  Brought on to assist in the investigation of Miami’s latest serial killer, Dexter Morgan (Michael C. Hall) becomes fascinated with “Trinity’s” unique killing methods and his ability to evade capture for almost three decades.

Holy crap... This sounds like a great, great fit for Lithgow's acting talents, and it'll be exciting to see him go up against Michael C. Hall. Season 3 hits store shelves on August 18th, while Season 4 will begins airing September 27th on Showtime. DEXTER stars Michael C. Hall, Jennifer Carpenter, Julie Benz, James Remar, David Zayas, Lauren Vélez and C.S. Lee.