John Lithgow on Board for Season Four of Dexter

Jimmy Smits guest-starred on season three of Dexter and knocked the role of Miguel Prado out of the park.

Now, sources confirm to Michael Ausiello that the Showtime hit has landed another major name to portray season four's main antagonist:

Look for John Lithgow to join the cast as Walter Simmons, a seemingly unassuming suburbanite who has been living a dual life as one of the country’s most prolific serial killers.

Dubbed the "Trinity Killer" because he always kills in threes, Simmons relocates to Miami and, as viewers might expect, Dexter becomes obsessed by this man's efficient killing methods, as well as his ability to evade capture for such a long period of time.

Season four of Dexter premieres on September 27.