As he celebrates his 99th birthday this week, Sir David Attenborough is marking the moment with what he calls one of the most important films of his extraordinary career. Ocean — a cinematic call to arms — premieres 6 May at London’s Royal Festival Hall, urging us to protect the world’s seas before it’s too late.

“After almost 100 years on the planet, I now understand the most important place on Earth is not on land, but at sea,” Sir David says in the film.

Drawing on a lifetime of storytelling, Ocean blends personal reflection with a powerful warning: our oceans are at a tipping point. The film exposes the widespread damage caused by industrial fishing, especially bottom trawling — a practice that not only tears through delicate marine ecosystems but also releases huge amounts of carbon dioxide, fuelling the climate crisis.

Toby Nowlan, the producer of Ocean, says this latest film marks a shift from Attenborough’s usual documentaries. “This is not about seeing brand new natural history behaviours. It is the greatest message he’s ever told,” he says.

But as with many of Attenborough’s films, hope is woven into the story. Ocean revisits the near-extinction of the world’s whales and the dramatic turnaround since commercial whaling was banned in 1986.

“I remember thinking that was it — we’d lost the great whales,” Sir David recalls. Yet decades on, their numbers are climbing again, proof that recovery is possible when the world comes together.

The release of Ocean couldn’t be more timely. With a major UN conference just weeks away (the high-level 2025 Ocean Conference in Nice, 9-13 June) world leaders face mounting pressure to honour their promise to protect a third of the planet’s oceans. If they act, the results could be transformative — for biodiversity, for climate stability, and for the generations to come.

“The ocean can bounce back to life,” says Sir David. “If left alone, it may not just recover — but thrive beyond anything anyone alive has ever seen.”