“Guardians of the Galaxy” director James Gunn has tapped “Frutivale Station” star Melonie Diaz for his new horror film, “The Belko Experiment,” set up at MGM.

Gunn made the announcement Wednesday on his Facebook page. He also revealed this week that “The Newsroom” star John Gallagher Jr. and “Scandal” star Tony Goldwyn have been cast as the male leads.

Gunn said he hired Diaz because of her work in “Frutivale Station.” “Her honest performance was exactly that kind of thing we were looking for for ‘The Belko Experiment,'” he wrote. “So when she said she was interested in playing Dany Wilkins, one of the leads of the film, I jumped up and down and punched my desk and some trash cans and my assistant Simon with pure joy.”

He went on to describe Diaz’s character. “Dany is the new girl at Belko. It’s her first day working in the building, and she really couldn’t have chosen a worst first day, since this is the day the employees are all forced to either kill each other or be killed.”

The story follows an American company after it’s mysteriously sealed off in South America. The employees show their true colors when they are ordered to kill each other or risk being killed themselves.

Australian director Greg McLean will helm “The Belko Experiment” from Gunn’s script. Gunn is producing with Peter Safran.

Gunn is also on board to direct and produce Marvel-Disney’s “Guardians of the Galaxy 2,” which has been slotted for May 5, 2017.