'Wayward Pines' season 2 cast news, spoilers: Melissa Leo talks about returning to (and exiting) series

The latest episode of FOX's "Wayward Pines" saw the brief return of season 1 star Melissa Leo.

In "Once Upon A Time in Wayward Pines," Leo's Nurse Pam came back to Wayward Pines and exited just as quickly. In the episode, Pam, overwhelmed with guilt from killing her brother David (Toby Jones) in the first season, returned and stole a vial of smallpox from Megan's (Hope Davis) facility. In her own macabre version of a murder-suicide, Pam injected herself with smallpox, trying to wipe out the entire town (and possibly all of humanity) in the process.

According to Leo, the reason for her ever-so-brief return was that, like former co-star Carla Gugino, her busy schedule would not allow her to come back for an entire season and the one-episode return was the best she could do.

Speaking with Entertainment Weekly about her guest star appearance on the FOX sci-fi mystery/thriller, Leo said that she had so much fun reprising her role as Nurse Pam and revealed that her quick stint at Wayward Pines was something she had been discussing with the people behind the series for quite some time.

"Once I settled in, I had a great time," the actress told EW about coming back to the set, adding, "Wayward Pines, I tell you, is a strange place, and the entry is always the hardest part."

"I was just going along for the ride," she said with a laugh.

Leo also admitted that returning to the series was "very strange," explaining that "Wayward Pines" was reinventing itself, as most television shows are doing nowadays.

"I'm interested in what the fans think," she said, adding that she wants to know what makes viewers feel connected to the series. "I had a lot of fun thinking about the first season," she shared.

Speaking of the show's first season, "Wayward Pines" executive director M. Night Shyamalan recently compared the show's sophomore season to its first.

In a separate interview with EW, the "Wayward Pines" boss said that aside from the fact that the new season features new characters, "I would say that because every character's waking up, they're having their own arc, so you get to watch all these characters go through initiation in their own way."

According to Shyamalan, season 2 "feels much more muscular, because the premise is outed."

"You can have more fun," he said.

"Wayward Pines" airs Wednesdays at 9 p.m. EDT on FOX.