Charles turned down role in Dr Who
Speaking at the Cheltenham Literature Festival on Sunday, writer and executive producer Russell T Davies told 2,000 sci-fi fans the prince snubbed his invitation to star in the popular BBC1 drama.
Joined onstage by actor John Barrowman, who plays Captain Jack Harkness in the hit series, Russell, who has the OBE, called the prince a "miserable swine".
Referring to his new book Doctor Who: The Writer's Tale, Russell was asked about his plans for a Prince Charles cameo in the time-travelling series.
He said: "He turned us down, the miserable swine."
Russell, considered to be the leading force behind the 44-year-old show's revival, recently announced his tenure as lead writer and executive producer would end next year.
The 45-year-old Welshman resisted giving away any secrets about forthcoming episodes to the crowd in Cheltenham.
But he did say he has decided what happens in the last episode he will be in charge of.
And while he doesn't know the final line, he said he does know what the second-to-last line would be.
Next year, instead of a full 13-part series of Doctor Who, there will be four special episodes – all starring David Tennant as the Doctor.
Parts of this year's Christmas special were filmed around Gloucester Cathedral earlier this year, co-starring David Morrissey.
And Russell also said he has been able to devote more time to Doctor Who spin-off series Torchwood, which returns for a five-part series in the New Year.
A spokeswoman for Clarence House said: "He didn't turn down the opportunity from Doctor Who. A letter was sent into our office here in Clarence House and was dealt with by officials on the prince's behalf.
"We receive a lot of requests and it's not possible to accommodate them all."
During his talk at the Centaur at Cheltenham racecourse on Sunday, Russell also revealed Doctor Who's real name is Keith.
Not a true world exclusive, unfortunately, but the writer's tongue-in-cheek response to the final query of a lively question-and-answer session.
Addressing the eager gathering, John Barrowman named Jon Pertwee, Tom Baker and David Tennant as his favourite doctors.
The 10-day literature festival, now in its 59th year, has seen a host of political figures, writers, actors and comedians take part in more than 350 events across 20 different venues.
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