London, UK - Heartstopper will be without one of its biggest stars heading into season 3, as actor Olivia Colman has confirmed she was not able to return to the TV show for its next batch of episodes.

In an interview with Forbes published Thursday, the 50-year-old Oscar winner sadly announced the news that she wouldn't be back as Sarah Nelson, mother to Kit Connor's character Nick.

"I couldn't do number three. I couldn't fit it in. I feel awful about that," she told the outlet.

Colman affirmed her love for the project, calling it "one of the most beautiful things" she'd ever worked on.

Kim Kardashian Inside Kim Kardashian's friendship with convicted killers Erik and Lyle Menendez

In response to writer Jeff Conway's pitch for her return in a potential fourth season, she remained optimistic.

"Okay! I'll have a word. As long as it's booked in advance, maybe I'll be able to do it, yeah," she said,

The news raised some alarm among fans of the Heartstopper graphic novels, as Colman's character was expected to play a key role in the upcoming storyline.

Author Alice Oseman took to Instagram on Thursday to assuage fan concerns in a series of posts shared on her story.

"We tried absolutely everything we could, but it wasn't meant to be, and that's just the way the TV world works sometimes," she wrote.

Oseman confirmed that Sarah would not be re-cast, adding, "Sarah's role as emotional support for Nick will shift to other characters in the story for now."

Elon Musk Elon Musk had "massive blowup" with Trump advisor during heated exchange

With renewal for a fourth season still up in the air, the showrunner affirmed that they would love to have her return if possible.

Over on Tumblr, Oseman further clarified that Sarah had not been written out either, with the crew instead shifting scene settings and taking her out of Nick's family vacation that takes place in Volume 4 of the graphic novels.

Amid news of Colman's absence, fans have been buzzing about several casting announcements and rumors, and according to Oseman, there are still more to come.

Season 3 will add Darragh Hand as Tori's new friend, Michael Holden, from the Heartstopper graphic novels and Oseman's debut novel, Solitaire. Bridgerton star Jonathan Bailey is also rumored to be coming on board as a scholar named Henry Maddox, whom Charlie had a crush on in a mini-comic, though the character's name appears to have been changed to Jack.

Heartstopper season 3 hits Netflix this October.