Matt Smith would have become "meaner" had he stayed on 'Doctor Who'.
The 31-year-old star, who bowed out of the titular role in the BBC sci-fi drama last Christmas, feels his incarnation of the Time Lord would have taken a darker path if he was still on the show.
Speaking at Wizard World Comic Con in Philadelphia over the weekend, he said: "If my Doctor had carried on he'd have become a bit meaner and a bit tougher. The universe would have weighed on his shoulders a little more which would have been cool."
Appearing intrigued by the idea of a darker Doctor, Matt quipped: "Damn, I should have stayed!"
Matt was reunited with his former co-star Karen Gillan, 26, during a fan panel at the event and the pair teased fans by hinting they may work together again in an adaptation of Shakespeare play 'Macbeth'.
Quizzed if he's ever played a Shakespeare character, Matt said: "I'd like to one day. I'd quite like to play Macbeth."
Karen added: "I want to play Lady Macbeth."
The flame-haired beauty's response prompted Matt to suggest: "Shall we do that together?"
The new series of 'Doctor Who', meanwhile, is currently filming and marks Peter Capaldi's debut as the Time Lord, taking over from Matt.
'Doctor Who' series eight is due to air in August.