When Dante Lam saw a six-minute clip of a documentary about marine rescue and salvage in 2014, the Hong Kong director－best known for his action blockbusters－was instantly hooked.

In the footage produced by China Rescue and Salvage, a national force administrated by the Ministry of Transport, Lam saw three rescuers descending down a steel rope hanging out of a helicopter hovering over the raging sea.

Facing off against turbulent waves, the rescuers risked their lives to save the screaming passengers and crew trapped on the hull of a sinking cargo ship, two-thirds of which was already submerged underwater.

"I watched the clip over and over again. It was extremely dangerous and I really admired the courage of the rescuers. It felt so thrilling to see the destructive power of nature, which I realized I could easily paint as the ultimate 'villain' in a movie," Lam says in an interview with China Daily.

His previous directorial forays, 2016's Operation Mekong and 2018's Operation Red Sea, yielded box office hauls of 1.19 billion yuan ($172 million) and 3.65 billion yuan, respectively, with the latter reaching the top of the box office charts. Lam is, to date, the highest-grossing Hong Kong director in Chinese-language cinema.

Yet, he was inspired to make a feature about marine rescue long before he signed up to make the two blockbusters, which made him one of the most sought-after Hong Kong filmmakers on the Chinese mainland.

The night before the interview, Lam had just finished the final edit of his latest action blockbuster, The Rescue, marking the culmination of a five-year-long aspiration.

As one of the most widely-anticipated releases and a likely box-office pillar for the upcoming Spring Festival holiday, The Rescue will open on Jan 25, the first day of Lunar New Year.

With a budget stretching to some 700 million yuan, the movie starring actor Eddie Peng and actress Xin Zhilei follows an elite team from China Rescue and Salvage tasked with saving survivors trapped in disaster situations and accidents, ranging from an oil rig that catches on fire and a natural gas explosion, to rescue efforts in a mountainous region hit by an earthquake.

As the largest-scale Chinese film to feature marine rescue and salvage operations, the crew built a vast film set on the beach in Xiamen, Fujian province, and traveled over 12,500 kilometers to shoot the main water scenes at Mexico's Baja Studios.

Originally constructed for James Cameron's epic Titanic, Baja Studios has some of the world's largest stages and filming tanks, and are famous for contributing to the cinematography of several water-dominated hit movies, including Michael Bay's Pearl Harbor and Peter Weir's Master and Commander: The Far Side of the World.

All the studio's tanks－the largest of which is 640,000 cubic meters and takes 54 hours to fill－were used during the shooting of The Rescue, which also saw the production team purchase and transport a retired Airbus 320 airliner from Las Vegas to Mexico.

"When I am determined to do something, I always use all my strength to pursue excellence. Once the scale and budget of the film was decided, I knew I had to provide the audience with a visual feast that they would surpass anything seen in previous Chinese productions," says Lam.

Unlike most of his peers who rely on CGI and indoor soundstages to digitally create disaster epics, Lam opted to shoot scenes on real-life sets to help the actors become immersed in their characters. He also demanded that the cast take part in rigorous training regimes to ensure they acted on screen just like the professionals do in real life.

This also earned the 54-year-old director the teasing nickname of "devil director" from Peng, who has worked with Lam on three previous occasions in Unbeatable, To the Fore, and Operation Mekong.

In an earlier interview, Peng－an A-list actor followed by around 33 million fans on Sina Weibo－recalls that he was required to join a team from China Rescue and Salvage for an entire month to receive his training, which was mostly underwater.

Peng also wore a suit made of heat-protective clothing to perform on a specially-constructed set to shoot the fire scenes, where temperatures reached as high as 600 C.

"Disasters occurring in water or fire are perhaps the most difficult to shoot. I insisted that these scenes were shot on real sets, as I wanted the reactions from the actors to come across as real and instinctive," explains Lam.

Talking about how Chinese disaster movies are still rare compared to Hollywood, he reveals that to shoot The Rescue he had to assemble special-effects veterans from five countries－the United States, Canada, South Korea, Germany and China－to design the stunts and handle the postproduction content.

"Speaking honestly, most of the talent from Hollywood are graduates of engineering. They can make precise calculations to guarantee the safety of the cast and crew. With its talent shortage, the Chinese film industry has yet to form a mature sector in this field," Lam says, extolling the skills of his multinational crew.

As well as the mind-blowing action sequences, the new film also aims to explore the complexity of humanity, says Lam, who assigned his scriptwriters to interview rescuers and document their words.

"One of my most impressive tales was from a rescuer who had to go out on a mission on the day that his father passed away. He was in shock from grief, but he said it was his duty to hurry to the scene to help people in need," recalls the emotional director.

"For me, it's interesting to discover that a hero who battles nature could also be the sort of ordinary person who lives next door. He could be a caring father or a concerned husband, but in a minute, he has the ability to transform himself into a fearless hero," says Lam.

A native who entered Hong Kong cinema during its golden era in the 1980s, Lam shot to fame from alongside Gordon Chan for codirecting the award-winning Beast Cop (1998), and he grew his reputation on the Chinese mainland with the success of Beast Stalker in 2008.

Now considered as a master of action films, Lam has shot epics set in the air, on the ocean and underwater. When asked what kind of place would spawn his next adventure, the director smiles. "I don't dare to think. I'm afraid that I wouldn't get (the go-ahead) to shoot such a film even if I had a great idea.

"For people like me, we just love cinema, and the process of shooting a film is enjoyable in itself," says Lam.