It's a sign of a great actor when, with just a small part, they manage to blow everyone away. Olivia Colman's professionalism and talent were never in question, but her short yet iconic performance in the LGBT+ series Heartstopper was even further proof of her skills.

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Heartstopper came out only about a month ago, and it soon became one of the most-watched Netflix shows, but no one could have predicted its success. Which begs the question, how did a series that was only just starting, based on a brilliant but new graphic novel, manage to get the Oscar-winning actress to play a supporting role in it?

8 Author Alice Oseman Thought It Was A Ridiculous Idea

Being Olivia Colman means having a plethora of complex, important roles to choose from, most of them lead roles. That's why it surprised the world when The Crown star selected a supporting role in this coming-of-age romance series. Not to say that Heartstopper is not a top-tier show, but the role they were offering Olivia was very small in comparison to the type of parts she's used to. So, of course, when producer Patrick Walters suggested Colman to Alice Oseman, the author of the book this series is based on, she thought it was the "stupidest idea ever."

7 The 'Stupidest Idea' That Was Brilliant

Despite her lack of faith, Alice Oseman allowed Patrick Walters to shoot his shot. The producer was very invested in the idea of having Olivia Colman in the show, and in his own words, it was "a dream."

"I was talking to Alice and suggested Olivia Colman to play Nick’s mum, and it felt like a total fantasy," Patrick explained. "'That would be brilliant, but that’s incredibly unlikely.' So we only sent the part to her, and she said yes!"

"I literally thought this was the stupidest idea ever," Alice added with a laugh. "I thought there was no way she would want to be a part of this or anyone famous would want to be a part of this. I was proven wrong!"

6 It Only Took Olivia Colman Two Days To Finish Her Part

Olivia Colman might have liked the premise of the show and her character, but she's still a very busy person, so she was only available to be on set for two days. That wasn't a problem, though, because, as everyone knows, she's a professional.

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So, in two days, she nailed her scenes to perfection, but her skills were so breathtaking that it seemed like she had been cultivating a professional relationship with star Kit Connor for a long time. Their chemistry on-screen captivated fans, and opened the door to new collaborations between the two actors.

5 Kit Connor Didn't Know Olivia Colman Was Going To Be In The Show

Maybe it was because the crew didn't want to say anything until it was a sure thing, or maybe they just wanted to surprise him, but for whatever reason, Kit Connor didn't learn about Olivia Colman's involvement in the show until it was almost happening. With all the secrecy, though, Kit assumed something big was coming. And he was right.

4 But He Knew Someone Famous Was Coming

"There was a circle on the call sheet like. 'Who is it gonna be?'" Kit explained. "I thought, 'Okay, it’s got to be someone really interesting.' They kept it secret because they weren’t sure if she was going be able to do or not."

3 The Character Moved Olivia Colman

Despite her short time in the show, Olivia got really in touch with her and Kit's characters. There is a scene in which they have a very heartfelt conversation that is very important for the mother-son relationship in the show, and the intensity of the script got to her.

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"In their scene when he’s coming out to her in the rehearsal she was just looking at Kit and his performance was so moving she just burst into tears and forgot her lines," Patrick shared in awe. "It was a kind of amazing dream."

2 It Was A Life-Changing Experience For Kit Connor

The making of the show in general was very meaningful for Kit, both in his professional career and in his personal life. But sharing the screen with Olivia Colman was the cherry on top. He didn't hold back when describing his experience with the actress and expressing his gratitude.

"We got to film with her for two days. It was really just me and her, and it was an utterly incredible, enlightening experience," he said. "I think it’s an honor for any actor to be able to work with an Oscar winner of this kind of caliber."

1 Olivia Colman Pushed The Other Actors To Be Their Best Selves

Everyone in the Heartstopper cast was great at their job, there's no arguing that. But having Olivia Colman there inevitably raised the bar. The cast, particularly Kit Connor, found themselves having to bring their A-game. Kit remembered in an interview how, only during their rehearsals, she was already impressing him.

"We were reading [the scene] through and suddenly a tear rolls down her eye, and we were only giving 50%!" Kit Connor explained. "And I was just thinking, 'Oh, god, I’m gonna have to step up my game now,' as if I didn’t already have to!"

Olivia Colman's time in Heartstopper might have been brief, but it was iconic, and she set a high standard not only for actors but also for parents. She portrayed the perfect example of an understanding, accepting mom that provides her children with a safe place to express themselves, and just for that, she deserves all the praise.

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