Funnyman Russell Brand was left red-faced on the London set of his new movie after a passerby pushed him into a fountain.
Filming on Get Him To The Greek ground to a halt after the prankster lunged at Brand, who flew into the pool in the British capital's Trafalgar Square.
The unidentified man then attempted to run away but security guards caught the attacker and held him until cops arrived on the scene.
Meanwhile, the stunned funnyman was ushered into a tent to recover, and was cheered by extras after re-emerging 20 minutes later to continue work on the Forgetting Sarah Marshall sequel.
An onlooker tells Britain's Daily Mail, "It only took a nudge, but the bloke used a bit of force. Brand was completely underwater. I expect he will have some bruises."
But the actor refused to press charges, and was quick to laugh off the incident, writing on his Twitter.com page, "I am refreshed. It's not the first time I've frolicked in that wretched fluid."
A spokesperson for the Metropolitan Police has confirmed no further action was taken against the raider.