How Ryan Reynolds Helped Blake Lively Prepare for the 'Athletic Event' of Filming 'The Shallows'

Blake Lively also reveals to PEOPLE which of her husband's movies inspired her to take the role in The Shallows

Photo: Gilbert Carrasquillo/FilmMagic

When Blake Lively needed advice for her upcoming thriller The Shallows, she didn’t have to look far.

Her husband, Ryan Reynolds, has starred in movies like The Amityville Horror, making him somewhat of an expert in the genre – and a great resource for acting guidance.

“We help each other with basic things from just helping memorize what we have to do that day to saying, ‘Hey there’s an emotional challenge in this, what do you think? You know how would you conquer this?’ ” Lively, 28, tells PEOPLE.

For The Shallows, Reynolds helped the leading lady prep for eight weeks of shooting in 4-foot waves.

“He helped me remember that this isn’t just an acting challenge, this film, but it really is a physical feat,” Lively says. “I had to be prepared for it being an athletic event, not just a film.”

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Not only was the prep work physically grueling, but Lively is also alone onscreen for the majority of the film.

In the upcoming movie, directed by Jaume Collet-Serra, Lively plays Nancy, a young woman who decides to go surfing in an isolated, Australian area. Things quickly take a turn for the deadly when she finds herself clinging to a giant rock yards from shore as a great white shark circles her.

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Lively says she was partially motivated by one of Reynolds’ movies – and one that also required him to virtually go solo onscreen – to rise to the challenge of carrying her own project.

“He also did a film called Buried, which inspired me in a lot of ways to do this film because I know what a rewarding experience doing an isolation film was for him,” she tells PEOPLE.

The Shallows hits theaters June 24.