John Barrowman has revealed why he thinks Captain Jack has proved to be such a hit with Doctor Who and Torchwood fans.

The actor, who was speaking to Metro to promote his new autobiography, I Am What I Am, which was released yesterday, was first introduced as the character in the main show back in 2005, and since then he has appeared in 10 Doctor Who episodes to date, as well as every episode of its spin off, Torchwood.

And Barrowman thinks that part of Jack’s success is down to the fact that the audience find it easy to relate to him and his ‘happy-go-lucky’ attitude towards life.

“I think it’s the fact I’m portraying somebody people can identify with,” he told the newspaper. ”Whether it’s because he’s omni-sexual or he’s proud of who he is – he doesn’t [care] about what anybody thinks.”

He continued: “If I had a formula, I would sell it! I’d be handing it out on street corners for £1.50 each. I have been absolutely overwhelmed by the popularity and success of Captain Jack.”