Is everything bad that happens on Torchwood Captain Jack's fault? We asked John Barrowman!

Is Captain Jack Harkness the secret villain of Torchwood? The formerly immortal time hustler certainly seems to have a nearly limitless dark past. But actor John Barrowman insists that Captain Jack always aims to do the right thing.

We caught up with John Barrowman, and he told us why Captain Jack can still hold his head up after what he did in Torchwood: Children of Earth. And he hinted that you may not like the ending of Torchwood: Miracle Day. We also talked to Eve Myles and Mekhi Phifer. Spoilers ahead...

When we asked Barrowman if everything bad in Torchwood is Captain Jack's fault, he said, "Possibly." But he insisted that everything Captain Jack has done was for the best. "That's the way he sees it." Jack is just trying to keep the planet safe, by any means necessary.

There are hints already that Jack "gave" the villains in Miracle Day something which allowed them to create widespread immortality. And it looks like we're going to get some heavy-duty flashbacks to Jack's past in the nineteenth century. But Barrowman hints that it may be more complicated than it looks: "Yeah, everything that comes up later is ultimately because of what happened. But here's the thing: It might not be what [Jack] did, it might be what somebody did to him."

So how can Captain Jack still keep his head held up high after he murdered his own grandson at the end of Children of Earth? This is the question we've been dying to ask Barrowman for ages, and here's what he said:

He didn't murder a child. He sacrificed the child's life in order to save the human race. Jack has always said that he will do whatever it takes to save mankind. The way I look at it, he did the thing that nobody else would do. Because if somebody were to ask you to sacrifice a child or a family member, you wouldn't have done it. You'd have let the world go to pot. Jack took the responsibility on, and unfortunately his grandson paid the price. [Captain Jack holds his head up] because he knows he has to do certain things that are not good, and he can hold his head up, although he holds a great deal of weight and pain and sorrow on his shoulders, and he tries not to let that show. You just have to get on with it. You make those choices and decisions, and you have to move on.

But at the same time, despite all this added weight, Barrowman says that if Captain Jack were to reappear on Doctor Who, he'd be the same carefree person he was when he appeared on Torchwood's parent series in the past. Even with all the terrible things he's done and experienced, he would be able to let go around the Doctor, because the Doctor is the leader and carries all the weight.

Jack has lived so long that he's bound to have done some terrible things over the years — and you have to wonder if immortality is inherently corrupting. Would immortality corrupt anyone eventually? Not necessarily, says Barrowman — it's all about how you deal with it. And in Miracle Day, we'll see that some people handle immortality wonderfully, while others won't. We'll also be seeing more of the dilemma of how to handle the terribly sick people who will never die.

"There's all those questions yet to be asked, and they will be answered. And also, how you see them answered... not everybody's going to like it," says Barrowman. "Not everybody's going to like the outcome." It's the sort of thing "where you go, 'Ooh, that's awful. But I love it!'"

Meanwhile, Eve Myles told us that she's excited to get to do so many huge special effects scenes and action sequences this time around — the trailer we saw at Comic-Con included Gwen blowing up a huge warehouse and riding away on her motorcycle. "I say it's like the best part of the job, you get to work and do those sorts of things." But Myles is also thrilled by a lot of the smaller character moments that we're getting this time around — scenes like Jack talking to the pedophile televangelist, Oswald Danes. "People you wouldn't expect to talk to each other."

This time around, Gwen may finally come to accept that she's stuck with Torchwood forever.

Torchwood has always found her, and it's become her drug. It's what makes her heart beat. It's what makes adrenaline rise up. It's what makes her sweat. And excited. And in that big scene where the rockets come in from the house and having that big jeep chase on the beach, and it's such a telling moment where she turns to Jack and there's the biggest smile on both their faces. 'Thank god for delivering me from boredom.' It's wonderful, but now she's a mum. She's a mum, and it's really different to juggle Torchwood with [motherhood.]

But at the same time, becoming a mother has made Gwen more fierce — like a lioness protecting her cub — and even though she was fearsome before, she fights that much harder now, especially when her daughter is involved. Myles is amazed at how much Gwen evolves throughout the series, even from episode to episode, becoming more of a rogue and more of a spy as opposed to a police officer. "Every day is different, there's a new threat every day. It's her and Jack. There's no-one else. They've got to do it. So she will use whatever she can use, she will do whatever she can do, to protect the human race."

On Doctor Who, we often see the companion studying to become another Doctor. We wondered if Gwen was Captain Jack's apprentice in a similar sort of way, and if she was learning to become another Captain Jack. But Gwen sees it as more of an equal partnership:

That's why they work so well together. What one is really strong at the other is very weak at, and vice versa. So they kind of fix each other, in a way. They complement each other... it comes together and it's a perfect package.

But don't hold your breath for the Jack-Gwen romance to blossom. "I think there's more interesting stuff [going on]," she says. "And I think if you put those kind of characters together, you ruin it, because the chase is always more exciting than the actual catch." Just like Mulder and Scully on The X-Files. "You don't want them to get together." Seeing Gwen and Jack sharing an emotional moment, like their phone conversation in episode three, is "far sexier, far more intimate than any sort of getting togehter, with the kissing and the snogging and all the stuff that goes with it. It's more psychological, and it's warmer, and it's more special, and that's more interesting to watch."

Also, Mekhi Phifer says that we'll be seeing a lot more layers of Rex Matheson soon. Rex is constantly overcompensating, because he is in a lot of pain and feels vulnerable. "He wants to be extra tough. He's the kind of guy who doesn't want other people to see that he's in pain, or what he's going through. He's kind of introverted in that way. He doesn't want to wear his heart on his sleeve in that way. So it's a lot of fun portraying him, because there are a lot of different levels." But we'll see Rex growing to trust the Torchwood gang more, and realizing that they actually do know what they're doing — and this might lead to Rex being more open with them.

Stay tuned for more of our Torchwood: Miracle Day interviews, including writer Jane Espenson and actor Bill Pullman, soon! A new Torchwood: Miracle Day is on Starz this Friday at 9 PM.