Ritter claims that MGK went 'ballistic' after he made a suggestion for his character in his film with Fox.
Ritter, the frontman of All-American Rejects and an actor in films including House Bunny and Peppermint, shared during a recent podcast interview on Tuna on Toast With Stryker that he was filming two different roles simultaneously: one as Tyler in Prisoner's Daughter with Kate Beckinsale and the other as Guy in Johnny & Clyde with Fox.
Ritter, 39, noted that he'd been struggling to tap into a scene in Prisoner's Daughter where his character has to lose it, but got some unexpected inspiration thanks to an interaction with Machine Gun Kelly, whose real name is Colson Baker.
Noting that his character in Johnny & Clyde is a "henchman" to Fox's character, Alana Hart, he shared that the actress' character likes to tease his character by putting her fingers in his mouth.
Ritter shared that he went to Fox's trailer when Machine Gun Kelly was there and suggested that in a scene where Fox's character dies, his character puts his fingers in her mouth as "resolution to my character getting his revenge."
He claimed that his suggestion caused Machine Gun Kelly to "go ballistic."
"Colson just goes from zero to raging, awesome, super angry. He was super bummed about me asking if I could put my fingers in Megan Fox's mouth," Ritter said. "He just went ballistic. He kind of went maniac mode."
Ritter called Machine Gun Kelly's confrontation the "greatest gift" to him as an actor because it helped him in his Prisoner's Daughter role.
"He had a baby's arm of a joint hanging out of his mouth. And he was fully unhinged. I was like, 'OK, man, I'm just going to receive you,'" Ritter recalled. "It was the greatest gift, and Megan was such a sweetheart."
Fox, 37, and Machine Gun Kelly, 33, have had their ups and downs. The self-proclaimed "twin flames" were the subject of split speculation earlier this year shortly after celebrating the one-year anniversary of their engagement.
In April, a source told ET that the couple were working on their relationship.
"Megan and Machine Gun Kelly are doing much better and are taking things day by day," the source said at the time. "They feel like they are ultimately meant to be together and they are working towards that goal. They believe they are soulmates and hope to build up their trust, honesty, and everlasting commitment to each other."
Since the split speculation, they've been spotted vacationing together, and Machine Gun Kelly told ET this month that Fox's Sport's Illustrated swimsuit cover was "hot," while supporting her at the publication's launch event.
And on Tuesday night, they were spotted holding hands in London after leaving the unveiling of Machine Gun Kelly's ring collection, The 8th Deadly Sin - GOSSIP with Stephen Webster.