Naomi Watts said she knew when she accepted her role in "The Desperate Hour" that it would be a difficult filming experience. "It was definitely a huge undertaking for me," Watts confessed in a recent interview with Looper. "I knew the physical side of things and the emotional side of things from the research."

Even though the actress was aware that a lot would be required of her for the project, the reality was nonetheless more than she bargained for due, at least in part, to the way the production was filmed that taxed on her both mentally and physically. "We discovered very early on that the best way to shoot it was to do these really long takes that meant I was covering two or three miles of ground and that I was doing 12 or 15 pages of dialogue," Watts explained. "That all added to the chaos and the drama and the tension and the unraveling of one's emotions. It was more than I imagined, and I imagined a lot. I certainly prepared for a lot, but the body doesn't work in the way that it used to, that's for sure."

"The Desperate Hour" is now playing in theaters, and is available digitally and on demand for rental or purchase.