Bree first appears in the season premiere Reversals of Fortune, as a new love interest whom Nate Archibald met over the summer. Once they arrive back in New York, they learn that their families are political rivals. As a result, they stay away from each other until Nate decides a way to rebel against the van der Bilts is to hang out with Bree at their charity polo match. He brings her and introduces her to his grandfather, William van der Bilt. After she realizes what he's doing, she asks him to keep their relationship on the down low because her family isn't speaking to her and she wants to change that. She explains that her cousin Beth Buckley, who she is very close to, was stood up at the altar and she was off rebelling and not being there for her.
Soon after, they hole up together in the Buckley's Manhattan apartment and spend 24 hours together to get to know each other (The Freshmen). After they realize how much they do like each other, they plan to come out as a couple at the Sotheby's Art Auction. They walk the carpet together and get photographed kissing. The next day, Bree catches up with Carter Baizen and tells him her family is still looking for revenge after what he did to them. She explains that she's headed home to see them, and they'll more than likely be in touch soon (The Lost Boy).
In Rufus Getting Married, Bree, Nate, Chuck Bass, and Blair Waldorf have brunch together. While they eat, Carter comes up and Bree excuses herself to make a phone call. Chuck follows, learning that Bree is looking for Carter for a reason. She asks him to find out where he'll be and let her know. Later, Chuck learns from Blair that Carter is staying at her penthouse with Serena van der Woodsen. He goes to offer him a ticket to leave town, and tells him to either tell Serena the truth about what he did to the Buckley's or leave town. At Rufus Humphrey and Lily van der Woodsen's wedding, Carter comes to tell Serena. He explains that when he was away he ran up a huge gambling debt, and then he met Beth. He figured her family was wealthy and could pay off the debt if it looked like he was going to be one of them, so he proposed to her. Right before the wedding, he realized he didn't love her and fled. Meanwhile, Nate learns that Bree was just using him to find out where Carter was. She admits to it, and says that she has too much Texas blood to let a fling ruin her relationship with her family. Afterwards, Nate breaks up with her and tells her to leave. This is Bree's last appearance in the series.
- Jeb Buckley (grandfather)
- PJ Buckley (cousin)
- Beth Buckley (cousin)
- She is older than Nate, as she was beginning graduate school at Columbia University when he was about to enter as a freshman.
- She's friends with her dad on Facebook.
- Nate pulled her hair at Bill Clinton's inaugural ball when they were kids.