Ron Perlman and Charlie Hunnam, <i>Sons of Anarchy</i> Ron Perlman and Charlie Hunnam, Sons of Anarchy

Sons of Anarchy star Charlie Hunnam made a major sacrifice for the second season of the FX drama: He lost a tooth.

"I'm sure it was worth it, but I've got a thing about my teeth," the English actor tells with a laugh. "My mum was really psychotic when I was growing up about taking care of our teeth. I don't have a single filling; I've never had anything done to my teeth, so it was kind of a bummer."

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The jaw-jacking scene won't hit TV screens until the middle of this season, but it comes as the tension between Hunnam's character, Jax, and SAMCRO leader Clay (Ron Perlman

) reaches fever pitch. Hunnam says Jax tries to avoid a physical altercation for as long as he can. "Jax tries to play an intellectual game with Clay rather than going in, guns blazing," he says. "But as his efforts get thwarted, his frustrations rise, and it all kind of comes to a head in a very violent fashion."Jax is still frustrated by the Season 1 murder of Donna, the wife of his best friend, Opie (Ryan Hurst). Donna died in a hit Clay ordered on Opie, but Jax keeps quiet for the sake of the club — much as he did when he helped Opie kill a Mayan gang member on whom Clay pinned Donna's murder in the Season 2 premiere."Jax felt some remorse, but at the same time, they are at war with the Mayans," Hunnam says. "There have been many casualties over the years at the hands of the Mayans, and this guy was a bad man, a gangster. He wasn't an innocent man — he was just innocent of that particular crime. I think Jax toiled with that, but his allegiance is to the club, and whatever needs to be done to protect his brothers is what's going to get done."

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Jax disposes of the body in a way that makes the murder look like the handiwork of yet another gang — a decision that has major consequences in Tuesday's episode (airing at 10/9c). "Jax thinks of himself as a lot smarter and a lot more able to run this club than Clay," Hunnam says. "And occasionally, there are these wake-up calls that [prove] it's not easy to make these big decisions. And inevitably, things are going to go wrong."One thing going (mostly) right for Jax this season is his relationship with Tara (Maggie Siff). "He's got the girl back, even though she had some pretty big reservations about jumping back into bed with Jax and this lifestyle," Hunnam says. "But, I think they've made the promise again that they are going to be together and do everything we can to make this work. I think Tara is always going to be conflicted about being drawn back into this world, but ultimately I think her love for Jax will win out."

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But Tara's involvement with Jax could make her a target for the white separatist leaders played by Adam Arkin and Henry Rollins. Hunnam says the gang rape of Gemma (Katey Segal) is only the beginning of the "miserable" deeds by SAMCRO's new foes."Adam Arkin represents the greatest adversary that this club has ever known," he says. "He comes in and causes a great degree of problems for us. But he is also in a weird, funny way, an ally to Jax, because he forces the club to fight them in a much calmer, smarter way. Brute force isn't going to win against this guy. So he helps advocate a mentality that Jax has been fighting for all along."So why, if cooler heads begin to prevail, do Jax and Clay come to blows? "There's going to have to be a reckoning at some point, and Jax tries to do it in a way that's the least damaging to the club," Hunnam says. "But it builds and it builds and it builds to this violent confrontation. It's a pretty hairy sequence, but I think it's worth the wait."And hopefully worth a tooth.