Megan Fox Roughs Up Boyfriend Machine Gun Kelly in First Trailer for 'Midnight in the Switchgrass'

Megan Fox found romance with Machine Gun Kelly behind-the-scenes of their upcoming film Midnight in the Switchgrass, but there was no love lost in front of the camera.

Fox, 35, roughs up her now boyfriend — whose real name is Colson Baker — in the first trailer for the crime thriller, which debuted exclusively with Entertainment Tonight.

She plays FBI agent Rebecca Lombardi, who crosses paths with a brutal serial killer while investigating a sex-trafficking ring with her partner Karl Helter (Bruce Willis).

Fox's character goes undercover as a sex worker in the trailer, when a would-be John (Baker) comes at her with a knife. But Fox holds her own, knocking the weapon out of his hand and bringing him to his knees with a few good punches.

Rebecca and Karl team up with Texas Ranger Byron Crawford (Emile Hirsch), who's been hunting down their suspect for years. But when Rebecca gets abducted by their target (Lukas Haas), Karl and Byron have hours to track her down.

The movie is based on the true story of Texas serial killer Robert Benjamin Rhoades (a.k.a. the Truck Stop Killer).

Producer and director Randall Emmett previously raved about the movie in PEOPLE's exclusive first look. "I am so fortunate to make my directorial debut with Midnight in the Switchgrass, and to work with such an extraordinary cast and crew," he said.

"You cannot go wrong when you pair actors such as Megan Fox, Emile Hirsh and Bruce Willis with an exceptional story of crime, deceit and suspense," Emmett added. "We can't wait to share it with the world."

Fox and Baker, 31, met on the Puerto Rico set of the film in March 2020.

"I don't know if people understand what a good actor he is," she said to ET of her costar-turned-boyfriend. "He is so charismatic and he's so naturally gifted and he's so intense."

The couple made their relationship Instagram official that July, after she appeared in his "Bloody Valentine" music video. The video came just days after her husband of almost 10 years, Brian Austin Green, 47, confirmed their split.

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The Jennifer's Body actress filed for divorce from Green in November, as she and Baker get serious. "Megan needs her divorce to be finalized before she can fully move on," a source told PEOPLE in January. "She is very happy though."

"They are very serious and plan on spending the future together," the insider added. "There will be an engagement at some point, but they are not engaged now."

Midnight in the Switchgrass premieres July 23.