The Reaping (2007)

"Thousands of years ago, there was a series of bizarre occurrences that many believe to have been the Ten Biblical Plagues. No one thought they could happen again. Until now."

Katherine Morrissey, a former Christian missionary, lost her faith after the tragic deaths of her family. Now she applies her expertise to debunking religious phenomena. When a series of biblical plagues overrun a small town, Katherine arrives to prove that a supernatural force is not behind the occurrences, but soon finds that science cannot explain what is happening. Instead, she must regain her faith to combat the evil that waits in a Louisiana swamp.