Simon Pegg played a radiation trick on co-stars Benedict Cumberbatch & Chris Pine while shooting Star Trek Into Darkness.
Pegg reprised the role of Scotty on the film, while Cumberbatch was a new addition to the cast list as be played Khan.
And the actor reveals that he played a trick on both Cumberbatch and Chris Pine whilst on set.
Speaking to The Sun newspaper the actor said: "I don't like seeing people get embarrassed. But we were filming in a nuclear facility and one day I said that Chris needed neutron cream - otherwise he'd get sunburn.
"He said, 'What?' And I said, 'Yeah, you'll get a rash from ambient radiation in the air.' From there the trick spread to other cast members.
"Finally, we got Benedict. He had this speech and he kept f***ing it up.
"Afterwards he said, 'Guys, I'm ever so sorry - I've got a real headache. I think the ions were getting to me.' He was so convinced."
Star Trek Into Darkness is the second Star Trek movie to be directed by J.J. Abrams and was a box office hit this summer.
Pegg is currently filming his latest project Kill Me Three Times with Teresa Palmer and Alice Braga.
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