On Once Upon a Time , we’ve seen characters transition from villainous roles to more heroic ones, but it’s often a struggle – and right now, it’s safe to say Mr. Gold/Rumplestiltskin has leaned back into his dark side in a big way.

Robert Carlyle as Rumplestiltskin in Once Upon a Time.

Robert Carlyle and Emilie de Ravin in Once Upon a Time.

Mr. Gold (Robert Carlyle) is always ready to lend a hand on Once Upon a Time.

During a recent visit to the set of Once Upon a Time, I was among a group of journalists who spoke to Robert Carlyle about his character’s conflicting natures and how and why his love for Belle may not be enough to permanently change him.I think it's always sort of precarious, you know, for him. Very little that he does is by accident. Everything is kind of pre-destined in some way. It's the same way in Season 4 that these characters come in to Storybrooke, the Frozen characters. He knows all these people, he has history with all of these people. So everything that's happening -- and the Snow Queen as well -- none of this is a surprise to him.I don't know how much I can really tell you about it other than they go way back. A lot of these magical characters, Rumple has either trained or helped in some way. He hasn't exactly trained her, but he's helped her along the way. There's a deep, deep history there, but there's a real strange relationship. They're very, very dangerous to each other. They're both slightly afraid of each other, I think.No, she's wouldn’t. Belle and him are two entirely separate things. It's wrong. You cannot combine these two characters together and think they're the same thing. There’s loads of stuff out there talking about “Rumbelle.” It doesn't exist. He is absolutely a character in his own right, as is she.He definitely loves her. There's no doubt about that and he wants to be with her. This other thing, [other] part of his life, is probably bigger. Because this has existed long before she came along and will probably exist long after she's gone. This hat and this kind of quest for magic and power is so massive for him. This kind of addiction he has to it is huge. That's what drives Rumplestiltskin more than love.That's his Achilles heel at the moment. I think it's a nice thing for the character to have. Any of these super powerful characters should always have something where if you pick below the surface, you can see there's problems there and that's his big problem. He's lied right away in his marriage, he's been duplicitous about this knife. I don't know, but I think once this comes up it's not good!If you think about it, that was a really stupid thing for Hook to do. And that comes back to bite him really badly. Because [Gold] knows as soon as it happened... he's already thinking "How am I going to do him for this?" and he does. And it continues after that. He won't let it go. He's like a dog with a bone. He gives him the hand, but...I guess, in a kind of simple form of looking at it, he's a villain; he's a bad guy. But it's very difficult when you live with a character for three or four years now, you can see lots of levels. I don't necessarily see him as purely a villain at all. I do see him as an addict. He's addicted to this world, this power and this magic. But I don't necessarily see him as being an evil person, though he’s done some pretty evil stuff and he's capable, he's very capable. And as it goes to episode 9 and 10, it's really bad, what he gets up to.I don't think the creators would ever let that relationship entirely go. But I think that this season it's going to stretch it to its limit. He's going to have to think on his feet all the time and try and keep these secrets from her. And we all know that's real life. You keep secrets from somebody and then another secret and another lie to make up for that lie. You tell another lie and another lie to make up for that lie. And that's where he is. So I don't think it can go on forever.