Sophia Bush, Hilarie Burton and Bethany Joy Lenz on Reuniting for 'Good Sam': 'Like Second Nature' (Exclusive)

The 'One Tree Hill' stars recall being back on set together to film Wednesday's episode and who else should drop by the CBS drama.

Sophia Bush with with her One Tree Hill pals, Hilarie Burton and Bethany Joy Lenz, on Wednesday's episode of Good Sam, the freshman medical drama she stars in and executive produces. In the hour, Burton and Lenz play sisters Gretchen and Amy Taylor, respectively, who cross paths with Dr. Sam Griffith (Bush) when Amy is admitted as a patient at Detroit's Lakeshore Sentinel Hospital. 

The onscreen reunion came about after Bush called up her friends with an idea for them to make guest appearances on the show. And, as the ladies explained to ET's Lauren Zima recently over Zoom, it was a very easy "yes." "It was a phone call and we were on planes like two days later?" Burton recalled. 

"It's funny because when we were doing press around the [show's] premiere in January, we're talking about the show and someone I was chatting with said, 'And Drama Queens. You've got your new show on TV and you and your best friends are doing this rewatch of your old show. Would you guys ever want to cross over?' I was like, 'All the time. Immediately. All I want is for my friends [to cross over] all the time,'" Bush said, referencing the trio's popular One Tree Hill podcast where they share behind-the-scenes stories.

"And [producers] Katie Wech, Joanna Klein, Jennie Snyder Urman -- these are the women who run my show. Katie called me and said, 'I saw your interview today and next week you'll have the script for [episode] eight, but there are these two sisters in it. Should we call Joy and Hilarie?' I was like, 'Yes! Of course!'" she recollected. "And then I was like, 'Wait... What are the roles? What do they do? I don't have any information!'"

Burton and Lenz both chimed in and said the roles didn't matter. "We don't care," Lenz quipped, prompting Burton to say they'd be in even if they were playing psychopaths. "Even better!"

"It's so much fun. We've all talked so much about the kinds of roles we want to play and we get asked by One Tree Hill fans and at conventions, 'What do you think each of your characters is doing now?' We've joked among the three of us and on the podcast that we especially would love to see Haley breaking the rules more often. So when I got the script for [episode] eight from Katie Wech, I was like, oh man, one of these sisters is real messy. Joy, do you want to play her?"

"And Hilarie... can tell you she really signed up to lean into the more conservative, square sister," Bush said. "She took it to the most delicious places. Watching Peyton Sawyer be all grown up in a sweater vest is a moment I will cherish for always."

Burton acknowledged it was "fun" to play a character who was on the straight and narrow for once. "It was fun to flip-flop roles. I always get cast as the jerk and Joy always is the sweet one. So this was a fun opportunity for me to get real square and for Joy. We had so much fun in the hair and makeup trailer. Me drawing tattoos on Joy... That was a fun day."

Ramona Diaconescu/CBS

The threesome shared what it was like being back on set together again when they filmed the mini reunion episode in late January.

"We were real hyper. I felt bad for all of Sophia's castmates because we are just, we're like a tornado when we're all together. We were so happy to be together," Burton shared. "We'd done a live event for Drama Queens back in October but it's rare that the three of us can be in the same place at the same time. Thankfully her cast was so gracious. And they had us come watch the episode with them and they were so nice to us on set."

"It felt like second nature though," Lenz added. "I mean, getting back in the hair and makeup trailer with you three. Yeah. We were hyper. We had a lot of fun but it was just, we fell right back into the old routine."

"Everyone was so excited for you guys to be here," Bush confirmed. "Also, so many people on the crew came up to me and were like, 'OK. So we're going to really play it cool because we really want to be respectful. And we know that these are your friends and also this is your place of work. But like, we're super big fans and when they wrap can we maybe ask for pictures? Like how does this work?' It was very, very sweet and people were so touched. My cast here has built such a great camaraderie and set family. They were like, 'This is so crazy to see your best, oldest friends from work come in here when we all feel that way and it's a preview of our future if we're lucky.' And it was, I mean, they could tell you, I cried the whole time. I was just like, 'This is really great, you guys.'"

But Bush, Burton and Lenz are constantly "tossing around ideas" over their text group chat for future projects to work on together. And one in particular -- an idea Lenz had during the One Tree Hills days -- may finally come to fruition.

"Just recently we all revisited it and we were like, 'Yes. It's time,'" Burton said, with Lenz confirming it may be a potential TV show that may or may not bring some tears. "If it's not deeply emo, would it be from your girls?" Bush joked.

Now that the door has been opened for One Tree Hill alums to appear on Good Sam, Bush has desires to bring on other co-stars in future episodes.

"We've been talking about how much we want Lee Norris to come. Also, Wendy Crewson plays my mom. Wendy Crewson and Daphne Zuniga could for sure be related. Daphne could be Wendy's sister. Sam needs an aunt," Bush said. "I want everybody to come. I want you guys to come back."

"I feel like y'all need some Antwon [Tanner] energy. Y'all could really enjoy that," Lenz said.

"I would love to get him in that hospital," Bush affirmed.

Good Sam airs Wednesdays at 10 p.m. ET/PT on CBS.

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