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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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."