Cold Feet star Robert Bathurst has blamed being bullied at boarding school for him becoming a "wary" and "very private" person.
The English actor was sent to a boarding school run by Benedictine monks at eight, and says he was bullied by staff and older pupils.
He told the Radio Times that when he was filming Mrs Brown's Boys D'Movie in Ireland, he hired a car to revisit the school - but was "hyperventilating" as he went up the drive.
Robert said: "Your letters were read and if you said anything against the school, you were beaten.
"It has forced me to be very private.
"You become cannier about how much you show and how much you display. I don't announce any ambition in advance of doing something. You become very much more watchful and more calculating.
"You're wary; you anticipate trouble. You work out how things might play and decide whether or not to show your hand."
The actor, who plays management consultant David in Cold Feet, also spoke about sometimes feeling "underused and underrated" in his career.
He said: "In the early 1990s, in the annual round-up, someone referred to me as the most underrated actor.
"But then I've never met anyone in the profession of any standing who isn't a bit gnarly about what parts they could have done."
The star also revealed he is often sceptical about how his fellow actors present themselves.
He said: "Everything is done for effect, with one eye on how it's going to be received. I never trust what an actor says."
This week's Radio Times is on sale on Tuesday.