The 28-year-old actress shot most of the film without the help of a stunt double, but what's more impressive is that she shot at least part of the movie while pregnant with her and husband Ryan Reynold's second child!
"They didn't hire a stunt double till the last two weeks of shooting," Lively explains in a behind-the-scenes clip. "Every single day there wasn't a single scene that wasn't stunt-heavy."
While filming began in November -- well before her pregnancy news -- Lively was snapped shooting additional scenes in Malibu, California, on April 12, two days before it was announced that she was expecting. Wisely, her later scenes weren't as intense
as the earlier ones.
"Doing the underwater sequences, I'm in 4.5-foot waves," she shares, describing some of her toughest days on set. "Whether I was in the tank or when I was in the ocean, I was about 300 yards away from shore. They would drop me off on this rock that was three feet by three feet."
In the film, that rock is the only thing that stands between her and a great white shark.
"You're in the wild. You are in the land of big, incredible, majestic wild creatures," Lively says. "And if you're wearing a wet suit, you're dressed as a seal."