John Barrowman is best known for playing Captain Jack Harkness: immortal leader of Torchwood, former Time Agent and companion to Time Lord Doctor Who. However time was limited for the actor, who was running between autograph signings, a panel, more signings and photo ops at Wizard World’s Philadelphia Comic Con this past weekend. But Barrowman invited me to be his own companion on a run between duties at the Pennsylvania Convention Center, and made the time to chat about Saturday’s news that Matt Smith would depart “Doctor Who” at the end of this year.

Barrowman -- who has further increased his nerd cred with his villainous turn on The CW’s “Arrow” – found out about the news while on a flight to Philadelphia. But the actor joked that he didn’t break down in tears over the news.

“I don’t know what the reaction is people want me to have but as an actor, it’s no big deal; it is a job for him [Smith],” he said. “I wasn’t devastated, I wasn’t gutted, but I am excited to see who the new Doctor will be.”

As for his own stake in the Whoniverse, Barrowman has been incredibly vocal about wanting to return to “Doctor Who.” His Jack Harkness has been a popular addition to the franchise since it returned in 2005 following its nine-year break. But Barrowman, who said he was not asked to be part of November’s 50^th Anniversary Special, hasn’t performed alongside Smith’s Doctor and won’t be able to.

“It’s not a question of me not being able to,” Barrowman corrected. “It’s a question of not being asked. It’s not my say.”

For audiences who have gotten used to Smith occupying the TARDIS for four years, Barrowman agreed the change would be an adjustment.

“I know ‘Doctor Who’ so well and know the Doctors are going to change, so I’m not devastated he’s going -- but it is sad for the fans.”

He added they will be able to make the transition to a new actor regenerating into the role, just as they’ve done 10 previous times, including when fan favorite David Tennant passed the torch to Smith in 2010.

“When David left, everyone was like, ‘Oh, it’s not going to be the same’ but it’s going to be OK,” said Barrowman. “You’ll just join along and be a part of it, as you always are.

Although he seemed to acknowledge that whoever assumes the mantle of the Doctor cannot assume viewers, specifically American ones, would accept them in the same way Tennant and Smith have been.

Having enjoyed significant mainstream news media coverage stateside, Smith has arguably become the most well-known actor in the 49-year-old series for American audiences. And Barrowman -- born in Scotland before moving to the States as a boy, who then returned to the United Kingdom in college – said he doesn’t know if the next actor will enjoy the same exposure.

“That’s up to not only the public to decide that, but the actor (or actress) who plays the Doctor,” he said. “They need to want to be a part of that.”

Barrowman’s mention of a potential female Doctor, currently a popular topic of speculation, opened up another question. Would Barrowman, who is openly gay and portrayed Captain Jack as omnisexual, want to see a non-white, male or straight actor cast as the Doctor?

“Oh my god, anybody, yeah!” he said. “But my opinion doesn’t really matter because I don’t write the show and don’t produce it, but I think a black Doctor, Asian Doctor, white Doctor, gay Doctor, a straight Doctor, a bi Doctor – whatever – I’m open to all that.”

Of course, for those who support him and lined up for hours for photos or autographs at Wizard World, and who are clamoring for a return of Jack Harkness, John Barrowman’s opinion definitely matters.

“I know; I’m part of the world, but in the world of ‘the suits,’ my opinion doesn’t matter but I know what you’re saying.”