How Heartstopper season 3 reworks tearful comic moment without Olivia Colman

In mapping out Heartstopper season 3, creator Alice Oseman knew she needed to include one crucial scene. It's a beloved moment from Oseman's original graphic novels, in which Nick (Kit Connor) has a tearjerking heart-to-heart with his mom, Sarah, on the beach about his boyfriend's struggles with anorexia and depression. "Love can't cure mental illness," Sarah tells her son in what is now one of the most recognized quotes from Oseman's work.

The problem was, as Oseman herself revealed publicly in March, Oscar winner Olivia Colman, who played Sarah across the first two seasons, could not fit a season 3 appearance into her schedule. "It's such an important, pivotal moment for Nick in particular, one of the really key scenes in that whole storyline," Oseman tells Entertainment Weekly. "I knew that conversation needed to happen, but sadly it couldn't be with Nick's mom. So I did have a backup plan at that point."

In the comics, Nick has an aunt and uncle, Diane and Richard, who appear briefly. Oseman did not include these characters in past seasons because, as she puts it, "they didn't contribute anything to the story." But what if now, with season 3, they did?

The team didn't have much time to fill the role of Aunt Diane, who's a therapist, when word came through that Colman's schedule conflicted with filming. They heard through their casting director that Hayley Atwell of Captain America and Mission: Impossible — Dead Reckoning was interested in Heartstopper. "She didn't audition. She's a very established actress and we knew that she would be amazing," Oseman says.

Atwell's casting was announced last April, and a description of the character also mentioned that Diane would take Nick on a summer holiday to Menorca, where she would impart some tough advice about his relationship with Charlie (Joe Locke).

"At that point, obviously, I couldn't just shove her into the story for that one scene. It wouldn't make any sense," Oseman explains. "So I had to go back, weave in some new scenes, introduce her as a character, help us to understand what her relationship is like with Nick, and then gently lead us towards this final scene that will make sense and that will still have that really emotional impact when we watch it."

Oseman knows that fans of her graphic novels are concerned about how the show will pull off this moment because of their emotional connection to it. She admits it was "definitely one of the bigger screenwriting challenges" in reworking it around Diane. "But I'm really happy with how it all turned out," she continues. "I think it works out really well and it makes total sense within the episode and it's really emotional."

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See the end result when Heartstopper season 3 premieres on Netflix this Thursday.