Astrange-looking woman in a wetsuit heaves herself up on to a gravel beach in a remote corner of Iceland. Her mouth is swollen and peculiarly wide, she has webbed hands and is wearing a huge black diving mask and flippers. She stops moving abruptly and lies still, not breathing, her arms and legs splayed out at odd angles on the pebbles. But as the camera zooms slowly in on her body and the actor Marianne Faithfull’s voice starts narrating, we learn that the webbed woman is not a woman after all. She is a fish. The scene is from Wild Summon, a 14-minute film that combines animation with live-action underwater photography, which has won multiple awards since it premiered at the Cannes film festival last year. It was nominated for the festival’s Palme d’Or for best short film before being shortlisted for an Oscar, and now it is up for a Bafta on Sunday. The main protagonist is a female wild salmon, who “in her last act of resilience” is giving her body back to the river she was born in. “Hidden in the pebbles, near her decaying body, are thousands of eggs,” Faithfull says in her distinctively raspy voice. Under the water, human foetuses bob up and down inside small red sacs. Each is wearing a black diving mask. “We call it natural history fantasy,” says the Bristol-based film-maker Saul Freed, who made the film with his wife and fellow film-maker Karni Arieli. The couple wrote, directed, shot, CGI-animated and produced Wild Summon, helped by their 14-year-old son Yuli, who was the primary drone operator and aerial cinematographer while they were on location in Iceland. “If you watch the film without the sound, it might look like some sort of science-fiction film about creatures that live underwater. If you do the opposite – if you just listen to the voiceover – then it’s a straight natural history documentary,” says Freed. As the title Wild Summon suggests, it is a film about a wild female salmon and her fight for survival as she migrates from a freshwater river to the open ocean – and then, in an impressive feat of physical endurance, all the way back to her birthplace to spawn her young. Nearly a quarter of the world’s freshwater fish are at risk of extinction, and Atlantic salmon are now classified as near threatened on the International Union for Conservation of Nature red list. In December, new evidence revealed that the species’ global population has fallen by 23% since 2006. Giving the female salmon a human body makes it easier for the viewer to empathise with her, says Arieli. “We wanted people to connect to this female journey. The female voice is telling them ‘this is a salmon’, but their eyes are telling them it’s a human woman.” The couple hope this innovative way of telling an environmental story may appeal to a new generation. “We’re huge fans of the [David] Attenborough genre, but that’s his genre, and he’s done that – so how do we move forwards and build on that?” Arieli asks. To ensure accuracy, it was important to the couple to shoot the backdrop of the film in the real locations in Iceland where salmon swim. So after doing some underwater training, they took Yuli and their younger son Teo, who was six at the time, on what Freed describes as a “family road trip filming event”. “For us, there was never any question that we’d have to be in the river,” he says. “We wanted to go and experience it. And for me personally, because I was the one in the freezing water, it was really physical.” Trying to keep his camera steady, he understood, in a very visceral way, just how powerful the river was. “You cannot stay still under that power.” On the last day of filming, sitting next to a waterfall, looking for empty water to shoot so they could add in their CGI “salmon-woman” later – the animated characters were composited into the footage they had shot in Iceland – they suddenly encountered a real-life giant salmon. “I swear to God it was my size,” says Freed. “It just jumped out of the water and flew into the air. It was an amazing moment.” A passionate wildlife photographer, their son Yuli is now studying film at college while Teo has decided that when he grows up, he wants to sing to whales. “What bigger gift can you give the next generation than a love of nature?” says Arieli. “Because if you love nature, you’re going to save it.”