In fact, many have already binged the series and have taken to Twitter to share in their shock and delight after discovering that a huge Hollywood A-lister appears in the show. Warning, spoilers ahead…
WATCH: Heartstopper season one is available to stream on Netflix now
Heartstopper tells the sweet story of two teenage boys named Nick and Charlie who strike up a friendship which quickly turns into a romance after they're assigned to sit next to each other in class. While the majority of the cast of the series is made up of newcomers, at the end of the first episode, it's revealed that Nick's mum is played by none other than Academy Award-winning actress Olivia Colman.
The news of The Crown actress' casting has been kept firmly under wraps by the show's cast until the series' release today - but it turns out they were also initially kept in the dark until it came to the day that the actress stepped onto set.
Olivia plays Nick's mum Sarah in the Netflix series
"We spent most of the shoot not knowing who was playing my mum," Kit Connor, the 18-year-old actor who plays Nick on the show, told HELLO!. "So it was like, there was a circle on the call sheet, who is it going to be? We thought, 'It's got to be someone pretty interesting.'"
He continued: "We got to film with her for two days. It was really just me and her and it was an utterly incredible, enlightening experience," adding: "I think it's an honour for any actor to be able to work with an Oscar winner of this kind of calibre."
She appears throughout the series in a supporting role
He added that it was also "nerve-wracking" trying to hold his own against the huge star in their one-on-one scenes, especially the huge moment which sees Nick come out as bisexual to his mum.
As he recalled: "I remember so distinctly sitting on the other side of the table, we were just stumbling through [the scene], and then suddenly a tear rolled down her cheek – and I just thought, 'I need to step up my game right now.'"
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Meanwhile, creator and writer Alice Oseman, who also penned the original webcomics the series is based on, never thought they would land such a huge name, describing the experience of working with Olivia as "so surreal".
"When we were discussing trying to get a big name to be Nick's mum, I was shocked when the actress wanted to do it. She's such an incredible performer and she brings so much to the character," she said. "She really connected with Kit who plays Nick and when they were rehearsing the 'coming out' scene she just cried because she thought Kit was so adorable!"
Taking to Twitter to react to discuss Olivia's role in the show, one viewer said: "When Olivia Colman showed up I actually screamed #Heartstopper." Another added: "And she did such a great job!! Hearing that 'Nicky' for the first time was tear-jerking! My fav on-screen mom for sure," while a third said: "Olivia Colman plays Nick's mum in Heartstopper?! Queen!"
Elsewhere in the series, there's also another cameo from a well-known name: actor and comedian Stephen Fry lends his distinctive voice to the role of Headmaster Barnes, who is never seen in the series but heard throughout on the school's intercom system.
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