Jonathan Bailey, Hayley Atwell and Eddie Marsan cast in Heartstopper season three

Jonathan Bailey, Hayley Atwell and Eddie Marsan have been cast in Heartstopper season three.

It was announced on Thursday that the three actors have joined the cast of the third season of Netflix's coming-of-age romantic comedy-drama TV series.

Hayley has been cast as Diane, Nick's (Kit Connor) aunt who takes him to Menorca for a summer holiday. Eddie will play Geoff, Charlie's (Joe Locke) straight talking therapist and Jonathan will appear as Charlie's celebrity crush, Jack Maddox.

In addition to Kit and Joe, the main cast includes Yasmin Finney, William Gao, Corinna Brown, Kizzy Edgell and more.

The official description of the upcoming third season reads, "Charlie would like to tell Nick that he loves him. Nick also has something important to say to Charlie. As the summer holiday ends and the months race on, the friends begin to realise that the school year will come with both its joys and its challenges."

The description continues, "As they learn more about each other and their relationships, plan social events and parties and start thinking about university choices, everyone must learn to lean on those they love when life doesn't go to plan."

In a new press release, the show's creator and writer Alice Oseman said she was "incredibly excited" to welcome the three actors to the cast.

"I am incredibly excited to be welcoming three new cast members to the Heartstopper family," she said. "It was an absolute joy to see Hayley, Eddie, and Jonathan's talent alongside our existing cast, and I can't wait for the Heartstopper fans to meet these new characters."

Season three, which will consist of eight episodes, will premiere on Netflix in October.