The House Next Door (2002)

Young marrieds Lori and Tom relocate from Chicago to the country where they end up living next to Carl, a right-wing radical who beats his wife, Helen. When Tom goes away for a few days, Lori, with the help of best friend, Monica, investigates the disappearance of Helen. Of course, this isn't the best idea, since it involves sneaking into gun-nut Carl's house in the middle of the night.