BBC News looks behind the scenes

Kit Connor and Joe Locke, who play Nick and Charlie, say their friendship means they support each other during the difficult days of filming.

Ann Gannon/BBC Actors Kit Connor and Joe Locke smile as they smile at the camera, both wearing Truham High PE ensembles from the series. Kit puts his arm around Joe. — Kit Connor and Joe Locke, who play Nick and Charlie, say their friendship means they support each other during the difficult days of filming.

On a frosty November day in 2023, we drive to a school on the outskirts of London. It appears to be unused and featureless, but a sign reading “Truham High” gives the game away.

This abandoned-looking building is actually the scene of a Netflix sensation Heart catcherand on the day of our visit, the shooting of the third series is already advanced. New episodes will be broadcast on October 3.

Inside, the bustle you might expect in a school hallway has been replaced by the organized chaos of a movie set. The modest interior of the school is covered with colorful murals painted in the style of Alice Oseman’s graphic novels, which became the inspiration for the show.

Mr. Ajayai’s art room is instantly recognizable.

In the first two series, Joe Locke’s character Charlie was a safe space he could go to when he was going through difficulties. During our visit, he is joined by Kit Connor, who plays Nick, and the conversation they record sounds difficult.

They sit in a corner and talk in hushed tones.

Heartstopper is famous for colorful settings like Mr. Ajayai’s classroom, but the walls and corridors are painted between seasons so that other TV productions can use them

Josh Parry / BBC The corner of the art room where Heartstopper was filmed. Countertops and sinks are covered with paint bottles, and there is a mural painted on the wall and along the window depicting a tree with autumn leaves, with roots painted on the floor — Heartstopper is famous for colorful settings like Mr. Ajayai’s classroom, but the walls and corridors are painted between seasons so that other TV productions can use them

While producers are tight-lipped about the details of the filming, they do tell us that “it’s a pretty intense scene.”

They keep an eye on how many people are in the room with the actors during more emotional scenes. Dozens of silent crew members crowd into an adjacent room, watching intently on monitors as the actors film several takes.

The third series of the show deals with more serious topics than the first two; A key plot point will be Charlie’s eating disorder, and some of the characters will have sex for the first time.

“We’ve always said that the show grows with the characters, and that’s definitely the case this year,” says Locke, speaking to us during a short break before the next scene.

“The show deals with more serious topics like mental health and growing up, so there’s a lot of ‘teenage’.”

The main plot of the third series will focus on Charlie, played by Joe Locke, struggling with an eating disorder

The series has been praised for showing “queer joy” – shining a light on the positive elements of growing up in the LGBTQ+ community – but Locke says it’s important to make sure it’s still realistic.

“It’s about authenticity and trying to create as true a representation as possible of a topic that is quite intense and close to people’s hearts,” he says.

Connor and Locke joked that it was hard to get used to kissing a friend on camera, and because the actors were so close to each other, they admitted that some of the more passionate scenes could feel strange to film.

Connor tells us, “When you’re shooting seven and a half hours like we did, for a scene that’s a little bit more exciting, I ask myself: what’s my job?”

During our visit, it became clear that the chemistry between the cast members extended beyond their screen time. During our interviews, they joke and gently make fun of each other, which Connor says helps during the more difficult days on set.

“After filming is over, we all just gather at someone’s apartment and hang out. We have a great way of doing it where we don’t talk about work or anything,” he says.

“We all just go home, make dinner and critique each other’s cooking skills.

“(Joe Locke) actually cooked good chili this time… last time it was very, very bad chili. This time, Will, who plays Tao, had seconds… but he will eat anything.”

Kit Connor and Joe Locke, who play boyfriends Nick and Charlie, say it’s hard to get used to kissing a friend on camera

Netflix/Heartstopper Season 3 A cameraman wearing a cap, with his back to the photographer, films Kit Connor and Joe Locke as they hug and smile at each other. Kit's red hair is wet and she wears a gray hoodie, while Charlie has dark brown curls and wears a loose green and white sweater. — Kit Connor and Joe Locke, who play boyfriends Nick and Charlie, say it’s hard to get used to kissing a friend on camera

While the friendships may be real, some of the show’s most iconic locations are actually flat-packed and assembled around the school as needed.

During our visit, Nick’s bedroom was assembled in what was once the school’s sports hall.

There are no lights because there are no scenes planned for today, so instead we explore using our phone flashlights. Even in the dark you can see the attention to detail.

From books about bisexuality to Polaroid photos of Nick and Charlie together, they made sure the bedroom was a true reflection of the character’s journey throughout the series.

“Fans really notice everything and have theories about even the smallest details… you should check out some of the TikToks they create,” a crew member tells us.

It may not look like it from the outside, but this wooden box is actually Nick’s bedroom in the show. Each set is built as needed in the school sports hall

Josh Parry / BBC A view from a film set supported by scaffolding. It is a wooden box with windows, and behind the windows there are artificial trees and bushes. The floor is covered with cables and filming equipment. — It may not look like it from the outside, but this wooden box is actually Nick’s bedroom in the show. Each set is built as needed in the school sports hall

Just down the hall from Nick’s packed bedroom is the costume department, where designer Adam Dee says he likes to give mega-fans things to notice.

“If they have a scene with an open wardrobe, we’ll sneak in some iconic elements from previous shows so viewers can spot them,” he says.

“Elle has a sewing station in her room, so we were able to add some little pieces to her wardrobe that are made up of two other items sewn together, or vintage scarves that we turned into tops.”

Heartstopper was a surprise hit for Netflix, and the first series launched with very little promotion.

Within two days of its release, it entered the top 10 most-watched English-language series and achieved an almost unprecedented 100% rating on Rotten Tomatoes – something many critics attribute to the film diverse representation on screen.

In the third season, some of the show’s older characters turn 16 and start having sex.

Season three will show the developing relationship between Elle and Tao (Yasmin Finney and William Gao)

Netflix/Heartstopper Season 3 A scene from Hearstopper where Elle and Tao are cuddling on Tao's bed. Elle rests her head on Tao's chest and they stare at something off camera. They are both wearing pajamas and lying on the duvet. — Season three will show the developing relationship between Elle and Tao (Yasmin Finney and William Gao)

Yasmin Finney’s transgender character, Elle, begins a sexual relationship with her on-screen boyfriend Tao (William Gao).

The sex lives of transgender characters are often left out of television storylines.

Finney tells us, “It’s nice to introduce a trans person who can have those kinds of relationships.

“It’s very nice and I’m very happy to do this performance with Will.”

In the second series, Tobi Donovan’s character Isaac discovers that he is asexual, meaning he experiences little or no sexual attraction. This is another topic that few TV shows cover.

BBC News was given exclusive behind-the-scenes access to interview the cast; including Toby Donovan (left) and William Gao (right)

Josh Parry/BBC A camera operator carrying equipment on her back points the camera at Obaj Donovan and William Gao, and a reporter pulls out a microphone to interview them. They both laugh. — BBC News was given exclusive behind-the-scenes access to interview the cast; including Toby Donovan (left) and William Gao (right)

Donovan tells us he wanted to do “a lot of research” to make sure he was “doing justice to this community.”

He added: “Nothing like this has ever been done on TV before, so I really wanted to make sure I got it right.

“I think from our reaction to season two, people were quite happy to even have someone on screen who was part of their story. It’s great for all of us.”

The cast told BBC News that the outdoor filming of the third series was “more popular” than the first series – with people stopping to watch and take photos

Netflix/Heartstopper Season 3 The cast of Heartstopper smiles at the camera while filming at the zoo. A giraffe and trees are visible in the background. — The cast told BBC News that the outdoor filming of the third series was “more popular” than the first series – with people stopping to watch and take photos

Just before leaving, we catch the show’s executive producer, Patrick Walters, on the set of Mr. Ajayai’s class.

Walters came up with the idea of turning back Alicja Osemana graphic novels into a TV series after “falling in love” with the books.

The diversity of the program is something he is particularly proud of.

He says: “It’s amazing that this is an important program for LGBT youth.

“I like to think that young people really see themselves in the characters and that’s why it connects.”