Machine Gun Kelly Shares Naked Behind-the-Scenes Look at 'Good Mourning' : 'Did 5 Whole Sit Ups'

The musician's new comedy, which also stars his fiancée Megan Fox, is now playing in select theaters and on-demand

Photo: Christopher Polk/getty

Machine Gun Kelly showed off more than just his acting chops for his new comedy Good Mourning.

The 32-year-old musician got naked for a behind-the-scenes look at his big-screen directorial debut on Saturday, all while partly covering himself with a washcloth. All of his upper body tattoos appear to be covered with makeup.

"I did 5 whole sit-ups (and 200 blunts) to prep for my role in Good Mourning. 💪🏼🎬," the "Emo Girl" rapper captioned the shot, which he shared on Instagram.

Kelly, who acts in the film under his real name Colson Baker, also shared a photo from one scene involving a water balloon fight. The rapper captured the moment a balloon burst against his cheek, spraying waves of water everywhere.

The rapper also shared plenty of cannabis-friendly content from the set of the stoner comedy, including a shot of himself and co-director Mod Sun squinting in surprise while posing with an enormous joint, complete with a little cartoon face.

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"This is your greatest post yet," Mod Sun wrote in the comments section (He is engaged to Canadian rocker Avril Lavigne, who also makes an appearance in the film as herself).

Machine Gun Kelly/Instagram

Good Mourning follows Kelly's character London Clash, a movie star who must choose between chasing his one true love or a once-in-a-lifetime movie role. His real-life fiancée Megan Fox also stars as his love interest.

Kelly previously opened up to PEOPLE about working with Fox, sharing that with very little direction, she brought her character Kennedy "to life."

"I'll always collaborate with Megan," the Mainstream Sellout singer gushed. "I'm madly in love with her — and I'm also a fan."

Pete Davidson, Dove Cameron, Becky G, Whitney Cummings, Zach Villa, Amber Rose, and Jenna Boyd also star in Good Mourning, now playing in select theaters and on-demand.