Kieran Culkin Recalls Getting Mark Ruffalo High in an On-Stage Prank: ‘I Was 17 and Stupid’

All the world’s a stage! 

Kieran Culkin, 42, opened up in a recent interview with The Guardian about getting Mark Ruffalo, 57, high while they were in a play together by swapping a prop joint for real-life marijuana. 

The Golden Globe nominee recalled being “17 and stupid” when he pulled the prank on opening night of the 2000 production of James Lapine’s play The Moment When with Ruffalo and Tony winner Phyllis Newman. 

But after he was hit with the smell of weed, he immediately felt regret. 

“I’m like, ‘I thought this was a good prank. I’m stupid. Oh my God, I’m so sorry.’ But actually, they loved it,” Culkin told the outlet. “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.’ ”

However, some people were less than thrilled about his stunt.

“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,’ ” the Succession alum said. 

A few years later, Culkin was doing Kenneth Lonergan’s play This Is Our Youth in London’s West End with Colin Hanks and joked about pulling the same prank, but Hanks said, “Are you f—ing kidding me? If you ever do something like that, I swear to God, I’m going to punch you in the face.”

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The A Real Pain actor continued, “But then towards the end of the run, I said it again and he shrugged like he was saying, ‘If you do, it might be fun.’ The thing is, his character has to roll the joint every night on stage. So, one day I hand him the real pot on stage and I see him, like, react. It looked like he was excited. But then he got too excited and got nervous. And his hands started shaking so much that he couldn’t get the joint rolled, and when he tried to light it, it fell apart. Thankfully, we had a pre-rolled fake joint behind him, so we ended up with that.”

Those in the theater don’t have to worry about what antics Culkin would get up to nowadays. “I’m 42 now. I know better,” he said. “I’m not going to try to get anyone high on stage.”

Ruffalo recalled the prank in 2020 during an appearance on The Graham Norton Show – though he did not name Culkin as the culprit.

“There was a play that I did where I had to smoke a joint in the first scene,” the Marvel star said. “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.”

Ruffalo explained that when you’re a stage actor, everything is exaggerated, so during his performance, he was taking dramatic puffs of the joint since he did not know it was real. 

“We smoked a giant blunt on stage,” he recalled. “I’m like, ‘Man, I am in it tonight, feeling it.’ ” 

He then recalled turning around and seeing “the kid who put the joint on the prop table” laughing.

“The girl that I was passing it to had never smoked pot in her life,” he continued. “I had, up to that point, smoked a lot of pot.”

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Ultimately, the prank came with some highs and lows.

“It was the worst thing I ever did. Don’t do it,” Ruffalo said, “but at the end of the play, I got the best reviews of my entire career.”