Brad PittClooney victim Brad PittBrad Pitt has given Ashton Kutcher the most invaluable piece of Hollywood advice possible.

It involves a certain prank-loving George Clooney and the words "Don't go there!"

Brad, interviewing Ashton for America's Interview magazine, heard that his young pal was cooking up a trap to get George for his MTV prank show Punk'd.

But he was adamant Ash should quit while he's ahead.

"I remember you were after Clooney. I would tell you as a friend, don't do it, don't ever go near it!" warned Brad, getting all serious.

"He'll kill you and everything you love."

Brad knows because he tried it once and got stung big-time.

G George Clooney Feb04Prankster George ClooneyWhile filming Ocean's Twelve, Brad convinced the crew to call George 'Danny Ocean', as he liked to stay in character even when the cameras were not rolling.

But George hit back harder - placing a sticker mocking the size of his, ahem, manhood on Pitt's car and then seeing Brad drive off through the LA rush-hour.

Ocean's Twelve co-star Matt Damon recently explained: "Brad was about to drive off and George came up to say goodbye.

"Brad was sitting in his car and George kind of tapped the car with his hand and said, 'All right, take care.'

"When he pulled his hand away, he'd left a bumper sticker that read 'Small Penis Onboard'.

"So Brad drove through rush-hour traffic in LA with it on, and all these people were looking at him and waving."

Ashton, you have been warned...