James Wan reveals the most difficult special effect in 'Aquaman' and it will surprise you

You won’t be surprised to hear that director James Wan didn’t actually film his actors swimming (or floating) underwater in Aquaman. But watching the movie, and especially seeing how the actors’ hair flows, makes you think, at least for a moment, that they might have. And how the filmmakers accomplished that look was one of the trickiest special effects in the CGI-loaded film.

“Part of the reason why we used the process [called] ‘dry for wet’ — which is literally what it sounds like, shooting it in a dry environment and using that to create the sort of underwater look and visage of it all — is we discovered very early on, when you’re underwater, you don’t actually look wet,” Wan explained to Yahoo Entertainment. “It’s only when you’re out of water that you look wet. When the water’s beading off your skin, you’re dripping wet, your hair’s [attached] to your face.

“And plus, on top of that, when you and I, when we move underwater, we move very slowly as ‘surface dwellers.’ But for Atlanteans, underwater people, it should not be like that. It should be so easy when they move underwater, right? It should be very graceful. So we realized that the physics of putting humans underwater did not make sense for us, for these people who are supposed to be superhuman. So we started working out methodology to create [an] underwater where they could move in a superhuman way.”

Speaking of hair, Wan also addressed a potentially controversial subject: Which actor has the best hair in Aquaman?

Is it Jason Momoa’s long locks? Willem Dafoe’s man-bun? Amber Heard’s bright-red mermaid look? His answer might surprise you. Watch the video above to find out.

Aquaman is now in theaters.

Watch James Wan talk about why he chose to direct Aquaman over the Flash movie:

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