Austin Nichols and Sophia Bush Austin Nichols and Sophia Bush

After eight seasons of bad boyfriends, One Tree Hill's Brooke is getting hitched.

No, really! Star Austin Nichols, who plays husband-to-be Julian, assures that disaster won't strike on their big day.

"Brooke's had a long journey in the world of romance and she's found the right guy," Nichols says. "I don't think anyone would come and mess with what we found."

One Tree Hill star: Get ready for Brooke's Hangover-style bachelorette party

Nichols joined the CW soap in Season 6 as a movie producer working with Lucas who also happened to be Peyton's ex-boyfriend. Since then, original love birds Chad Michael Murray (Lucas) and Hilarie Burton (Peyton) have left, and the romance between Nichols's Julian and Brooke (Sophia Bush) have taken center stage.

Neither Murray nor Burton will return for the wedding episode, but Nichols says there are no hard feelings.

"This is a strange business. You do a show or a movie and you get close with people and all of a sudden they're gone," Nichols says. "This show has moved on and found something different so I'm not sad, I'm happy for [Murray and Burton]."

One Tree Hill: Brooke, you've come a long way, baby

Like his character, Nichols is also contentedly in love. Die-hard fans of One Tree Hill already know that he and girlfriend and co-star Bush kept extremely busy during the series' long winter hiatus. After responding to the BP oil spill and raising money to help the many families and wildlife affected by the natural disaster, the pair was rewarded with the Sustainable Design Award from actor Edward Norton, who sits on the board of Global Green. Nichols credits the global fanbase of One Tree Hill for getting the word about their newfound passion.

"Our show is so international and some of the fans write to us and say the news doesn't cover anything about this. It was disturbing that a disaster of this magnitude wasn't being covered around the world like it could've been. We were amazed some kids heard about it through us," he says.

Check out photos from One Tree Hill

Nichols and Bush also created a compilation album for iTunes titled "Gasoline Rainbows" with the proceeds going to Global Green. Artists including Damien Rice, and Vampire Weekend lent tracks to the album.

"I never planned on being an activist," Nichols says. "There was a moment where something happened and you could no longer just sit around."

One Tree Hill returns with new episodes Tuesday at 8/7c on CW.

For more scoop on One Tree Hill, follow @RobynRossTVG on Twitter.