EXCLUSIVE: Gabriel Ebert (Ricki and the Flash) and Rarmian Newton (Rise) are set as series regulars and Glynn Turman (How To Get Away With Murder) will recur on the upcoming third season of AT&T Audience Network’s critically praised drama series Mr. Mercedes, from Sonar Entertainment. Production on the Stephen King adaptation is underway in Charleston, South Carolina.

Season 2 took place a year after Brady Hartsfield’s (Harry Treadaway) thwarted attempt to perpetrate a second mass murder in the community of Bridgton, Ohio. Since the incident, Hartsfield had been hospitalized in a vegetative state. Retired Detective Bill Hodges (Brendan Gleeson) did his best to move on from his Brady obsession, teaming up with Holly Gibney (Justine Lupe) to open Finders Keepers, a private investigative agency. But when unexplainable occurrences began to affect hospital staff members attending to Brady, Hodges was haunted by the feeling that Brady was somehow responsible.

Ebert will play Morris Bellamy, intelligent, well-educated if not middle class, a volatile and charismatic wolf in sheep’s clothing. When he was younger he had ambitions of becoming a famous writer but ended up with a much less exciting life in Ohio.

Newton plays Peter Saubers, 16, smart and personable, he’s a junior in high school and on the college track. From a seemingly happy home, but that picturesque Midwestern life was derailed when his father was disabled during the Mr. Mercedes massacre.

Turman recurs as Judge Bernard Raines, the no-nonsense judge presiding over Lou Linklatter’s murder trial, he suffers no fools and takes no prisoners. He is none too pleased with the lawyers working on this case who seem hell bent for trial.

David E. Kelley (Big Little Lies, Ally McBeal) returns for Season 3 to oversee the writer’s room and Jack Bender (Lost, Under the Dome) to direct. In addition to King, Kelley and Bender, Marty Bowen and Wyck Godfrey of Temple Hill Entertainment, Tom Lesinski and Jenna Santoianni of Sonar Entertainment, and Shane Elrod and Kate Regan of AT&T Audience Network will continue to serve as executive producers.

Ebert appeared in recent guest-starring roles on Instinct and The Blacklist and in features Ricki and the Flash, and upcoming The Devil All The Time. He’s repped by UTA.

Newton was one of the leads in NBC’s Rise and recently recurred on Tell Me A Story at CBS All Access. He’ll next be seen in a recurring role on AMC horror drama series NOSA42. He is repped by Gersh, Active Artists Management, Atlas Artists and Felker Toczek Suddleson Abramson.

Turman can currently be seen on How To Get Away With Murder and in upcoming roles on The Red Line for CBS and in the Netflix feature Sextuplets as well as alongside Ben Affleck in the Warner Bros. film The Has Been for director Gavin O’Connor. Turman is repped by The Rosenzweig Group and SMS Talent.