How do they do that? Divers 'walk on water'

The underwater film was shot by biologist Armiche Ramos and brothers Armando and Francisco del Rosario, who used their expertise in freediving to create the illusion.

No computer graphics were involved in the production, with the team relying solely on their own skills - and a few hidden secrets.

“We didn't use any special effects, just camera tricks and weights which were hidden inside the wetsuits," said filmmaker Ramos.

“We are always training hard, swimming, free-diving, doing yoga and running. This kind of experience is necessary to balance your body underwater.”

“People who watch it usually don't known what´s happening, they think that the images are made by computer. But we all have been free-diving since we were children.”

The trio, known as the Ocean Brothers, created the footage for underwater photography competition World Shoot Out, where it was awarded the prize for best short film.

The footage was shot over three years in El Hierro, which is the smallest of the Canary Islands.

But there were a few hitches, including postponing filming for a year because of an active underwater volcano.

He said: “The location is not always calm and we had to wait for the correct moment for several months at a time. 

“We had to stop production for one year because the eruption of an underwater volcano in the south of El Hierro, which turned the water brown and killed the sea life. We spent more than three years filming.”

In such dangerous conditions, the 36-year-old said it was imperative they followed every safety precaution.

He added: “The dangerous moments are when we´re tired, when we could make mistakes. But we always ensure that safety comes first.

"If the sea or the weather is not enough good, we don´t work, we just train instead.

“We usually dive with our friends who take on the role of security diver. So there are no real scary moments. We just try to have fun.”