In the original Star Wars trilogy, the good guys and the bad guys were very clear. On the light side were Luke Skywalker and friends. On the dark side were Darth Vader and his boss, the Emperor. But in Star Wars: The Force Awakens, some of those lines may be blurred.

Here’s what the actors say about their evil alter egos.

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Adam Driver, best known as the peculiar boyfriend on HBO’s Girls, plays Kylo Ren, a black-masked knight with a fiery red lightsaber who vows to “finish” what Darth Vader started. “We didn’t really have a lot of conversations about bad or evil, actually, when we were shooting it,” Driver said at the San Diego Comic-Con. “It was more what do you think is the difference between being bad and being right, which I think is a huge difference … That’s almost more evil, a group of people who decide that they’re morally justified for behaving a certain way. That’s how we kind of approached it and less like a bad person.”

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Gwendoline Christie, the towering knight in HBO’s Game of Thrones, is inside the chrome armor of Captain Phasma, commanding a legion of Stormtroopers for what’s left of the Empire, now called the First Order. “She is a Boba Fett-style character, striking and in command but not at the very forefront of the action always,” Christie says, comparing Phasma to the beloved bounty hunter from the original trilogy. “Other than that, all I can say is that she is badass.”

Domhnall Gleeson, formerly the brave older brother to Ron Weasley in the Harry Potter films, is General Hux, leader of the First Order’s Starkiller Base, which seems like the next generation of the Death Star. “I think General Hux would just like a little bit more order in the universe,” he said, understating the character’s obsession with power as he jockeys against Kylo Ren. “Whatever it takes is where he’s at.”