New Documentary Explores Cornwall’s Extraordinary Octopus Boom

When filmmaker and diver David Palfrey dropped into the waters off Cornwall, he expected a typical week of leisurely diving. Instead, as he sank beneath the waves, he found himself face-to-face with an underwater enigma: octopus after octopus, out in the open water, watching him right back.

Those unexpected encounters with this most enigmatic of sea creatures became the spark for Bloomin’ Octopus! A Tentacular Spectacular, a new short film exploring the ‘octopus bloom’ off the southwest coast of England in 2025. With divers and fishermen now reporting increased numbers of octopus appearing again in 2026, the film comes at a pivotal moment. As the story of the Common Octopus (Octopus vulgaris, usually seen in Mediterranean waters) continues to unfold, these out-of-the-blue interactions, in fact, raise urgent questions about warming seas, changing marine ecosystems, and what these shifts mean for coastal communities and the future health of the ocean.

“I’d planned a week of diving in Cornwall with a friend. Right before we left, we started seeing social posts about octopus, but we tried not to get our hopes up. Then we got in the water and the reality exceeded anything we imagined,” David remembers. “Dive after dive, there were octopus out and about, and what struck me was how curious they can be. They’re often shy, but sometimes they’ll interact, investigate, and seem to watch you as much as you watch them. Afterwards, there was this buzz everywhere – people asking why this was happening, whether it was a population boom, what it meant for crabs and lobsters…I couldn’t stop thinking; there’s a story here.”

David knew that there was a fascinating film to be made about the octopus, but also knew that it needed to have a grounding in hard evidence. The octopus hadn’t just turned up for no reason – there had to be something more behind it – but what?

“I spoke to fellow filmmakers but couldn’t nail the right angle. Meanwhile, the story kept moving, and I realised waiting for the ‘perfect’ plan was the wrong approach, so I decided to just go for it,” he explains. “I’ve wanted to make an alternative kind of science communication film for a while: something with pace and personality that might reach people who wouldn’t normally click on a lecture or a report.”

Palfrey’s personal footage and curiosity met that hard evidence when he discovered the Marine Biological Association (MBA)’s report documenting the scale, causes, and consequences of the 2025 bloom. The report also came about from talk about unexpected appearances by octopus in fishermen’s crab and lobster pots. The octopus weren’t just curious, they were deliberately entering the pots and killing and eating the catch. All the fishermen were seeing when they hauled up their pots were empty shells, and the occasional sated octopus still in situ. The MBA worked with partners to create a survey, which they sent out to fishermen along the southwest coast, asking for their experiences of octopus and the impact on their livelihoods, and the evidence was overwhelming – thanks to warming seas, octopus were moving in large numbers from their usual habitat and feasting on the finest seafood that Devon and Cornwall had to offer.

This was what David had been looking for. He contacted the report’s lead author, Senior Research Fellow and University of Plymouth Associate Professor Dr Bryce Stewart, and asked if they could work together to build the story around the data. As a prolific science communicator, Bryce was more than happy to help.

Blending documentary footage with stylised visual sequences, Bloomin’ Octopus! A Tentacular Spectacular balances humour and energy with community-led observations to create a story of interconnected experiences. From fishermen and fish market sellers to divers, snorkellers, and restaurateurs, the film weaves these stories together and, rather than offering a neat conclusion, it invites audiences to consider the uncertainty of ecological change happening in real time.

The southwest’s octopus surge began to build in 2024. By 2025, it was impossible to ignore, as fishermen reported octopus infiltrating pots and preying on valuable catches such as lobster, crab, and scallops. As Bryce says: “They’re quite the connoisseur.” Bryce appears in the film to help bring the science behind the bloom to a wider audience, connecting what’s being observed in the water to what the data shows about ocean warming and wider ecosystem change.

“The octopus bloom is an extraordinary event that tells us a lot about how marine life is responding to a warming ocean,” he says. “When David approached me with the idea for the film, I was impressed by his energy and creativity, but more than anything, by his determination to work with the MBA and use the evidence from our report to tell the story in a uniquely engaging way.”

The return of higher octopus numbers in 2026 keeps the spotlight on a fast-changing ocean. Scientists are continuing to investigate what’s driving the bloom and what it means for shellfish stocks, wider food webs, and the resilience of coastal livelihoods. The film is a starting point for that conversation, bringing viewers into the story at the moment it’s still unfolding.

David says: “My hope is that the film entertains first, because that’s how you reach all sorts of people. If it makes you laugh, or gets you leaning in, maybe it also gets you thinking about changing seas and the ripple effects on wildlife and coastal communities. And if you’re lucky enough to meet an octopus in UK waters, I hope you come away with the same feeling I did; wonder… and a few new questions.”

Bloomin’ Octopus – A Tentacular Spectacular is available on YouTube now.

Director: David Palfrey | https://www.davidpalfrey.com/

Research: Marine Biological Association | www.mba.ac.uk