Kieran Culkin Admits to Swapping Mark Ruffalo's Prop Joint with Real Marijuana During 2000 Play

The actor, reflecting on his teenage prank, revealed the incident led to unexpected onstage reactions and memorable performances.

Kieran Culkin confessed to switching a fake joint with a real one during the 2000 off-Broadway production of 'The Moment When,' where he acted alongside Mark Ruffalo and others.
The prank, which occurred when Culkin was 17, resulted in Ruffalo and other cast members unknowingly getting high onstage during a performance attended by critics.
Ruffalo, who had not smoked marijuana in a decade, later described the experience as leading to one of his best-reviewed performances, though he would never repeat it.
Other cast members, including Phyllis Newman, reacted with humor, while the stage manager reprimanded Culkin, telling him to 'ruin your life on your own time.'
Now 42, Culkin reflected on the incident as a youthful mistake, emphasizing that he no longer engages in such behavior and has since matured.