Heartstopper creator was drawing Nick and Charlie during cameo

Oseman appears in the eighth episode, where she can be spotted sharing a train carriage with her two lead characters, working away at something on her tablet as they admire the passing scenery.

In a Twitter post, she has revealed that she was drawing Charlie and Nick in the style that they appear in the Heartstopper comics – which fans found completely adorable. See the behind-the-scenes images below.

Oseman's appearance is not the only surprise in Heartstopper's first season, as the team behind the show also kept Academy Award winner Olivia Colman's role top secret until the day of release.

The team behind the show couldn't believe their luck when Colman agreed to be in the show, admitting that they had thought it was a long shot that their offer would be accepted.

Oseman recalled: "When we were discussing trying to get a big name to be Nick’s mum, I was literally like, there's no way this is going to happen. This is the silliest idea ever. There's literally not any point doing this.

"But we tried anyway and Olivia wanted to do it. And I just couldn't believe it. There's really no other way to say it, I was just shocked, but so happy because she's such an incredible actress."

Heartstopper has a cast comprised largely of newcomers, with Colman and comedian Stephen Fry being the most established names, the latter of whom has a voice role as a school headmaster.

Heartstopper volumes 1-4 are available for purchase on Amazon.

Read more: Heartstopper soundtrack: Every song in Netflix's LGBTQ+ drama

Heartstopper is available to stream on Netflix. Check out more of our Drama coverage or visit our TV Guide to see what's on tonight.

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