Teen Wolf's Theo will get a cold reception when he returns to Beacon Hills.

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A lone werewolf looking for a pack, Theo (Cody Christian) attempt to link back up with some familiar faces from his childhood as he tries to make inroads with Scott's (Tyler Posey) pack. While they may have known each other in the past, Stiles (Dylan O'Brien) will not be at all thrilled that the 19-year-old senior is back in town.

"I can tell you that my character hates him. That's immediately how I felt just now when you even brought his name up. There's a little Stiles in me as well," O'Brien teased, according to Celebified. "Yeah, I don't like Theo and I feel like there's something up with him...Stiles has eye out for Theo. He's a guy that we used to know growing up and he wants to be a part of Scott's pack. I'm very protective and I don't like him."

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This wouldn't be the first time Stiles was wary of another werewolf. It took him quite some time to warm up to Derek (see video below), and he never did quite get along with Jackson, Aiden, and Ethan. Unlike those four, however, it doesn't appear that Theo will start off looking like such a villain - it will be up to Stiles' copper gut to determine if he's a threat to his best friend.

However, the hyperactive teen will feel a twinge of remorse as he keeps a skeptical eye on Theo.

"At the same time I also feel bad about kind of being a jerk to him because what if he turns out to be a good guy?" O'Brien explained.

Find out more when Teen Wolf returns to MTV on June 29.