John Lithgow Joins Showtime’s 'Dexter'

Emmy-winning actor John Lithgow is joining the cast of Showtime’s serial killer drama Dexter. Lithgow, who starred in the NBC sitcom 3rd Rock From the Sun, will appear in all 12 episodes of Dexter’s fourth season, which will debut on Showtime in September.

Lithgow will play Walter Simmons, a.k.a. the Trinity Killer, a mild mannered suburbanite cum serial killer, with a penchant to kill in threes.

Simmons relocates to Miami after being tracked by FBI special agent Lundy (played by Keith Carradine), where Michael C. Hall’s Dexter takes intense interest in the killer, who has been able to avoid capture for more than three decades.