Scottish actor David Tennant has been left a "nervous wreck" by fame - because his job makes him focus on his insecurities.
The former Doctor Who star is one of Britain's best talents, but Tennant reveals he is wracked with doubts when comparing his work to his fellow actors - and his low-self esteem has left him nervous about failing to live up to expectations.
He tells the Radio Times, "It's a fear of failure. I admire other actors' work and then see mine and it seems false and crass.
"As an actor, you put yourself up for appraisal on a regular basis, asking for your insecurities to be tweaked. It's no wonder I'm a nervous wreck."
Tennant reveals that he decided to quit his acclaimed role on the classic British sci-fi show over fears he'd be typecast, as well as wanting to escape the huge publicity the series attracts.
He explains, "I wasn't bored but I wanted to quit before it became a job. Mercifully, I haven't been typecast and it opened more doors than it closed.
"I lost a certain amount of privacy. I'm not moaning, because there are huge advantages, but you do end up feeling vulnerable."