Exclusive: How the Cast of 'Black Rock' Bonded

A girls-only getaway to a beautiful, remote island turns into a fight for survival in the edge-of-your-seat thriller Black Rock, out on DVD next Tuesday, and we've got an exclusive look behind the scenes to see how the cast formed such a tight bond given the intense subject matter.

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"We shared something in those weird 18 days we spent in Maine," says screenwriter/actor Mark Duplass. Co-star Lake Bell agrees, "It forges the friendships -- that's why we kind of can't let go of each other as friends. We feel like we've been through the trenches together."

Kate Bosworth, Bell and Katie Aselton (who directed and wrote the source story) play childhood friends who set aside their personal issues to reunite for a weekend on the island they used to go to as kids off the coast of Maine. But when it turns out the island isn't empty, a seemingly innocent arrangement quickly turns into a deadly fight for survival.

Bosworth adds of the intense shoot, "I am a firm believer that nothing great comes easy, and I truly feel like Katie's made something special with this film."

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Black Rock comes out on Blu-ray and DVD July 30. Special features include audio commentary with director/actress Katie Aselton and actress Lake Bell, plus a look at the movie's thrilling score and a "making-of" featurette.