The Shallows: Blake Lively talks bikinis, why she never saw Jaws

Blake Lively has battled Upper East Side snobs (Gossip Girl) and some fairly nasty drug dealers (Savages). But she faces her most brutal opponent in The Shallows (in theaters now). Lively plays Nancy, a med student who goes on a surfing trip to Mexico and finds herself in a fight for her life against a great white shark. EW talked to the actress about the film, doing her own stunts, and getting in bikini shape.

ENTERTAINMENT WEEKLY: Talk about the plot a bit. Obviously, it's about a shark attack.

BLAKE LIVELY: I go surfing on an emotional trip, a trip to get away. I've experienced a loss and I'm trying to feel more connected to my mother and this is a beach that she always went to and she always told me about, an infamous beach and very elusive as well. So she tracks down this beach and she goes surfing and…then there's a shark. [Laughs]

It's an interesting thing because she's running away from demons in her life. Because of global warming, great whites that were in deeper water are now in much more shallow water. It's a very real very present thing. It's something you don't hear as much. It's very easy to villainize a shark like, "These monsters! We have to get rid of them." But it's also incredibly ignorant and irresponsible to think that way. We're in their land. It's just about being respectful and being educated.

She's surfing and she comes upon a shark's feeding ground and a whale carcass. She swims into that, and as any wild animal would do, when food is scarce and times are tough, here something is on its feeding ground and it protects its territory. Both of them are just battling to stay alive. Neither one of them is evil, necessarily — they're both fighting each other for their lives.

Nancy clings to a buoy for a pivotal section of the movie. What was that like to shoot?

There's only a small bit of it on the buoy and only a small bit of it in a bikini, thank goodness. That was what I worked out for. It kicked my butt. But I also wanted to work out not just for extreme vanity but because they didn't hire a stunt double until the last two weeks. So I was doing all my own stunts, not my own surfing. I did my best with surfing. We had the best junior surfer in the world surfing for me. My mom was like, "You should tell people you did that!" I said, "Mom, that's like me being like 'Oh, the Water Lilies — I painted those."

But I did my own stunts until the last two weeks. It's such a physical movie. There's a scene where I'm swimming up to the buoy and I crack my face under water and my nose is pouring blood and that was real. That happened. I wasn't supposed to crack my face underwater. It was just this thing is crashing into the water with these four-foot waves and I couldn't see, my perspective was off. The waves pulled me the same time that the buoy crashed down and cracked my nose and blood was pouring out. I thought I'm going to keep going during this take unless I pass out because I want them to see what they did to me! I want them to see how determined I am! I'm very proud of my bloody nose. I was in so much pain for a week.

Was the shark all CG? Or was there a mechanical one?

Yes. It was like pink tape x's that I had to react to. We filmed in the ocean and we also filmed in a tank. They had a big foam one for water displacement. The other thing that they had was they had a guy with a great white sized fin attached and he would swim around on like a little sea doo, like an underwater rocket propeller. But he would lose perspective too in the water and he's going in circles and he would get dizzy so he often would just crash into the walls [of the tank]. It was so awful but also you can't help but laugh. We were all trying to keep it together.

Everyone talks about filming on water being challenging. Was it really hard?

Yeah, filming on water is so tough because the elements are just relentless. It's freezing in the morning. It's so hot in the middle of the day. When we were in the tank, there were so many chemicals my skin would just fall off. I had all this makeup, like the bruise and the cuts and it would all fall off in the chlorine of the water. Then you're rubbing against these rocks and these buoys. Your body is just really taking a beating. It's an incredibly physical movie. When you read the script, you say, "Okay I'm not so much getting myself into a film as much as an athletic event. Also, emotionally it's an athletic event. You have to stay at that level of survival for two months straight, 12 hours a day. It was a huge undertaking but also rewarding. Every single person on that set is in the elements. Everyone is jumping in the water. Everybody is in the sun. Everybody is dealing with lightning storms. Everyone is on their toes and part of the same taxing mission. The connectivity you feel with that is cool.

Was that hard to be just you alone, having no one to play off of?

It was really difficult because all you have is your imagination. My husband did a movie called Buried and that was one of the reasons why I wanted to take on this movie so much because I know how tough that was for him and how rewarding it was. It was terrifying and one of the most vulnerable things you can do but you got to do it, right?

And you get to be kinda badass, which must have been cool.

Oh yeah. It was fun! It was fun to feel like I could get out there. It was less about the action star moments and more about the stunts I had to perform and feeling like I'm just a giant oversized golden doodle puppy and I feel so clumsy and then to get out there and do those stunts and be able to pull them off. I felt athletic and that was neat.

Are you more afraid of sharks now? Or less?

I was terrified of sharks. I never even watched Jaws because I was so scared of sharks. I went diving with great whites maybe five years ago and that was one of the greatest experiences I've ever had. It was really eye opening. You see these creatures in their habitat, not hunting you. They're just swimming in the ocean. You get to observe them as they are. There's such a peacefulness to them and such a beauty to them.

It was really neat to see them in a humane way rather than see them as monsters. That's what I connected with this film: Here she came to their territory. You never surf alone. You never go at that hour. She went up on the shark's feeding ground. You see the shark has a hook in her mouth. You see the shark has been hunted too. It's really a story of us all trying to survive on this planet. It sounds lofty but when you boil it down that's what it is. That's what I really liked about this is that it wasn't just bikini versus monster. But you still get a little bikini and you still get a little monster! [Laughs]. But we tell a more responsible story than that. That's what I connected with.