Mandy Moore has a few tips for surviving a shark attack after starring in "47 Meters Down," a new movie about great whites circling two women, you guessed it, stuck 47 meters deep in the ocean.

"I think you're supposed to get as close to the bottom of the ocean as possible," Moore told TooFab. "To sort of camouflage yourself into the ground."

Moore is on the big screen alongside "Originals" and "Vampire Diaries" star Claire Holt in the underwater thriller, in which the duo are stuck in a cage off the coast of Mexico after what was supposed to be a fun underwater expedition on vacation goes horribly awry.

Holt, on the other hand, had one simple idea for anyone that's stuck in a similar situation, "Pray. Say a prayer."

Moore admitted they're "not professionals" by any means, but is pretty sure "you're supposed to poke the shark in the eye if it gets close to you."

"47 Meters Down" is quite a departure for Moore, now best known for heart wrenching NBC drama "This Is Us." The shark attack movie is her first horror movie, and according to the actress, she couldn't imagine a scarier premise.

"I think that's what drew us to be a part of this particular movie," Moore told TooFab. "First of all, it's entirely unique - there really hasn't been another film that takes places 95 percent under water, and this really ultimately is a story of survival...when faced with unthinkable circumstances - being trapped in the bottom of the ocean, in a cage, with sharks circling, running out of air, not knowing where their boat is, not knowing where they are ... it's pretty much the most terrifying premise I can think of, personally."

The film was shot almost entirely under water, yet Holt and Moore said there was no intense preparation for the production, outside of some basic online training courses.

"We did a diving course, but we didn't learn too much about sharks," Holt said. Moore added that though the film was shot underwater, all of the sharks were computer animated, so using their imagination was key during filming.

And that leads TooFab to imagine it's not the best idea to trust Moore's previously mentioned shark attack tips.

"47 Meters Down" hits theaters this Friday.

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