By Will Robinson
Updated May 13, 2016 at 11:01 PM EDT
  • Movie

The good news about Jennifer Lawrence’s new Mystique costume? Marathon makeup sessions are no more. The bad news? She had to pee into a funnel, leaving her vulnerable to James McAvoy’s BB gun attacks.

The duo appeared on The Graham Norton Show ahead of the release of X-Men: Apocalypse later this month. A harmless question about Lawrence’s on-set transformation into the blue mutant Mystique revealed she ditched the full-body makeup in favor of something akin to “blue pantyhose that goes around my whole body that I can’t sit to pee in.”

Costar McAvoy exploited Lawrence’s predicament, via a running cast BB gun prank. “I’ve actually burst into her bathroom with a BB gun while she was trying to pee in a funnel,” he cackled.

“It’s so hard to do!” Lawrence exclaimed, “because you have to stop while you’re in the middle of peeing to let the rest of it go — it’s a whole scientific process.”

See Lawrence and McAvoy tell the full story above, while Norton winces.

X-Men: Apocalypse opens May 27.

X-Men: Apocalypse

  • Movie
  • PG-13
  • 143 minutes
  • Bryan Singer