Sure, he’d heard about the scathing reviews for Glitter. So Fringe star Lance Reddick didn’t know what to expect from Mariah Carey when they filmed the indie flick Tennessee.

But after their first scene – in which he shoves her up against a wall and grabs her face – the actor was pleasantly surprised.

“She pulled it off,” Reddick, acclaimed for his acting chops on HBO’s The Wire, tells PEOPLE. “She really took it seriously. She was committed to proving that she could do this.”

In the movie due out in January, Carey plays a waitress named Krystal, who tries to escape her abusive husband, portrayed by Reddick, by going on a road trip with two brothers.

Says the actor: “I saw all the subtlety in her work, and it’s really beautiful.”

Adding that Carey is “very sweet” in person, Reddick says, “After this, I think she’s going to have a film career, if she wants one. She is good.”

Also good? The success of Reddick’s FOX show, Fringe, where he plays a no-nonsense Homeland Security officer.

But, says Reddick, “We goof around a lot,” noting that Dawson’s Creek alum Joshua Jackson is a a big jokester.

Source: PEOPLE Magazine