This is the moment revellers dressed as Bananaman bumped into Professor Stephen Hawking while on a stag do in Cambridge.
Groom-to-be Chris Hallam, 29, and ten friends were all on a night out in the town, dressed as the comic book character, when they bumped into the professor getting out of his car.
And they were stunned when the Brief History of Time author agreed to pose with them for a souvenir photograph.
Chris, a self-employed builder from Norwich, said: "We only came across Professor Hawking because we were lost. We were just looking for a bar and spotted him getting out of his car.
"His son was with him and asking him 'Should we ditch the meal and go out with these boys?' They could have just told us to carry on but they were all brilliant.
"It's been mad. People just keep saying 'I can't believe it, is it really him?"
Father-of-one Chris is due to marry fiance Kizzy Davis, 34, on March 29 and says he will never forget his stag.