That's the hard lesson "Transformers" star Shia LaBeouf learned in London recently when he was beaten up for filming a girl vomiting on the street.
According to The Sun, LaBeouf (who's in London to film the Brad Pitt movie "Fury") was in Leicester Square when he and friend happened upon Ash Nawaz and her sister. The actor started filming them throwing up on the street, but when they objected, a stranger intervened. The other party, incensed at getting filmed as well, reportedly punched LaBeouf and kicked him in the groin. (Ouch.)
Security from a nearby club separated the men; LaBeouf and his friend took off. Later, Nawaz told the Sun, "I only realized it was Shia after he'd been beaten up. If I'd known, I'd have let him film me as much as he liked. I have a massive crush on him."
This isn't LaBeouf's first run-in with British locals. In 2012, he scuffled with a student over a baseball cap.
LaBeouf and London clearly don't get along.