Rhys Coiro joins new faces Charlotte Rampling and Sean Patrick Flannery in the Showtime serial killer drama.

Dexter is adding A Gifted Man and Entourage alum to its ranks.

Rhys Coiro has been tapped to guest star in an episode of the Showtime serial killer drama, The Hollywood Reporter has learned.

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He'll play a tough bail jumper that Deb (Jennifer Carpenter) is tracking in the upcoming eighth and potentially final season of the Michael C. Hall starrer.

Coiro becomes the latest addition to Dexter. Charlotte Rampling and Sean Patrick Flanery, who play a psychiatrist who works with young psychopaths (gulp, Harrison?) and a PI, respectively, are set to recur on the upcoming season.

The casting comes during a busy month for the actor, who was a regular on CBS' A Gifted Man. Coiro last week booked a co-starring role in CBS' Toni Collette drama pilot Hostages. He's repped by UTA, Untitled and attorney Dave Feldman.

Dexter shifts to a summer run and will premiere premiere at 9 p.m. on June 29 on Showtime.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit