There's a scene in Christopher Nolan's Dunkirk that begins with a sense of relief, as troops board a ship to return to England. But it's short-lived: The ship is soon hit with a torpedo and sinks.

Nolan's overall approach was to film on location as much as possible. So the director won permission to tow an actual French destroyer — the Maille-Breze, built in 1957 — out to sea off the coast of France. "We shot as much as we could, but there were limitations; it was an actual ship," says special effects supervisor Scott Fisher. "We ran a cable and pulled the prop torpedo and did the initial water explosion next to the boat."

They then filmed the actors at Falls Lake on the Universal lot with a replica of the ship on a gimbal, created by production designer Nathan Crowley. That's where most of the practical effects — the ship rolling and sinking — were filmed. VFX supervisor Andrew Jackson of Double Negative says digital effects were used where those shots needed new backgrounds or extensions of the sea in order to match the location. Finally, the interior of the ship was constructed on a set in the tank at Warner Bros.' Stage 16 in Burbank that then was flooded to film the trapped men.

It was all shot with Imax 65mm film cameras, handheld, by cinematographer Hoyte Van Hoytema. "There were a lot of pieces to this puzzle," he says, adding that the goal was to communicate a false sense of security and the "relentlessness of the event. When they get off the beach, the interior of the ship is warmly lit. Then there's a sudden absence of light, and it turns into hell and disorientation."

Editor Lee Smith used the editing to further that “emotional roller coaster — that element of complete surprise and then being incredibly disoriented — being in the hull and not knowing which way is up.”

Completing the experience was the sound. Says supervising sound editor/designer Richard King: “It’s relatively quiet underwater — mostly just the sounds of struggling men and debris banging about. Above deck it’s all shocking noise and chaos. The sinking ship groans, screeches and screams like a dying animal as it starts to break up.”

A version of this story first appeared in the Jan. 25 issue of The Hollywood Reporter magazine. To receive the magazine, click here to subscribe.