“The prodigal son returns.”

Taylor Dearden’s Dr. Melissa “Mel” King and Patrick Ball’s Dr. Frank Langdon instantly became a fan-favorite TV duo when The Pitt premiered last January. Now, the two are back together onscreen for the show’s second season, which premiered Thursday, Jan. 8.

Dr. Langdon had an abrupt exit in the debut season, as he was booted from the Pittsburgh Trauma Medical Center after being caught stealing drugs from the hospital. The new season opens with him returning to the scene following a brief stint in rehab.

In an exclusive interview with PEOPLE, Dearden, 32, describes the characters’ reunion in the first episode as “sweet.”

“I just thought it was sweet. Even though she knew him for one day, 10 months ago, he’s still someone who made a mentor impact on her,” she says. “I think getting someone back who feels like they might have a little bit more of an idea of who Mel is, was like, ‘Oh, I needed that validation of another human getting her.’ “

The reunion occurs when Dr. King is getting a rundown of patients with her colleagues. The group stops to talk to one who took a fall while riding his bike in his neighborhood. After the patient reveals that he wasn’t wearing a helmet, Dr. Langdon interjects, “You should always wear a helmet.”

The group of healthcare workers casually greets him, but Dr. King gives him an extra warm welcome.

Dr. Mel approaches Dr. Langdon with her arms in the air as she calls his name. Stopping just short of a hug, she embraces his arm with a wide smile on her face. Dr. Langdon, meanwhile, meets her enthusiastic greeting with a neutral expression.

“Sold to Dr. Langdon,” an attending physician says before proceeding with business. As the other doctors move on, Dr. King is shown lingering in Dr. Langdon’s presence for a beat.

Speaking about the tight bond between the two doctors, Dearden says, “I think Mel has always wanted a mentor. To have someone who was also willing to learn her just really made him the top of her list.”

However, the actress isn’t reading into the duo’s relationship as romantic. “Platonic relationships are not shown enough. One of my best friends is a guy. It’s really sweet as it is,” she says.

Each season of the hit medical drama follows a team of healthcare workers in a Pittsburgh emergency room during a 15-hour shift. The sophomore season takes place during a busy Fourth of July day in the hospital.

Noah Wyle returns as Dr. Michael “Robby” Robinavitch, along with Katherine LaNasa, Supriya Ganesh, Fiona Dourif, Isa Briones, Gerran Howell and Shabana Azeez. The second season also welcomes a few new faces, including Sepideh Moafi, Meta Golding, Luke Tennie and Christopher Thornton.

Dearden, the daughter of Bryan Cranston and Robin Gale Dearden, says she felt more comfortable on set during season 2 because she was aware “how the trauma scenes would go.”

“The first time we were like, ‘We have no idea or any context of how this is supposed to go or anything,’ ” she explained, adding that to have “the first time behind us” was reassuring.

The Pitt season 2 premiered Jan. 8 at 9 pm ET on HBO Max. Episodes air every Thursday until the finale on April 16.