Kieran Culkin Got Mark Ruffalo Stoned During Live Performance

Kieran Culkin admitted that he once tricked Mark Ruffalo and other co-stars into getting stoned during a live theatrical performance.

“I was 17 and stupid,” Culkin said in a recent interview with The Guardian. The incident occurred in 2000 while he was performing with Ruffalo and Phyllis Newman in James Lapine’s off-Broadway play The Moment When. The show’s opening sequence required Ruffalo, Newman, and a third actor to spark a fake joint and pass it between them while reciting their dialogue. Backstage was a large bag of faux pre-rolls, with dozens rolled in preparation for future performances. "The temptation was too great to switch one with the real thing," Culkin admitted.

Since only one joint was smoked each night, it was anyone’s guess as to when the real weed would rise to the top. Unfortunately, the cast’s consumption of the actual joint coincided with press night, when critics and media personalities were invited to view the show. Culkin recalled smelling the odor of marijuana and thinking, “Uh-oh. I believe it’s happened.” The actor, who is garnering Oscar buzz for his performance in A Real Pain, “just watched” as Ruffalo took gulping, theatrical hits off the joint.

Immediately, Culkin felt regret. "I'm like, 'I thought this was a good prank. I'm stupid. Oh my God, I'm so sorry,'" the Succession star recalled, expecting that at intermission he’d be read the riot act by his co-stars.

"But actually, they loved it,” he revealed. “Mark says, 'I haven't smoked pot in 10 years; the second half's going to be so much fun.' There was this other actor who had never smoked pot in her life. She goes, 'Is this what being high is? This is lovely.' And then Phyllis Newman comes in and goes, 'I haven’t smoked pot since the 1960s. Thank you, darling.'"

But while the cast may have been pleased about the turn of events, the backstage crew wasn’t nearly as elated. “Then the stage manager comes stomping in and goes, ‘I don’t care whose it is, or what happened, but Kieran, give me the joint. I sheepishly handed her the roach and she said, ‘Ruin your life on your own time.’”

Ruffalo addressed the incident during a 2020 interview on The Graham Norton Show, calling Culkin “a very naughty actor” without directly naming him. "There was a play that I did that I had to smoke a joint in the first scene," he explained. "And of course, there was a very naughty young actor I was in the play with, who on the opening night with all the critics, he slipped a real joint onto the prop table."

The 57-year-old took several long puffs before he realized he had “smoked a giant blunt on stage” and noticing “the kid who put the joint on the prop table” giggling offstage. "I just went, 'Oh s--t.' The girl that I was passing it to had never smoked pot in her life," Ruffalo continued. "I had, up to that point, smoked a lot of pot,” he admitted. "It was the worst thing I ever did. Don't do it," Ruffalo told Norton, before adding: "But at the end of the play, I got the best reviews of my entire career."