Anna Pigeon, a U.S. Park Services ranger, sets off on vacation—an autumn canoe trip in the Iron Range in upstate Minnesota—accompanied by her friend Heath, a paraplegic; Heath’s fifteen-year-old daughter, Elizabeth; Leah, a wealthy designer of outdoor equipment; and Leah’s thirteen-year old daughter, Katie. For Heath and Leah, this is a shakedown cruise to test the new cutting edge line of camping equipment Leah has designed, which will make camping and canoeing more accessible to disabled outdoorsmen. When Anna returns from a solo float on the Fox River, she finds that four heavily armed thugs have taken her companions captive. With limited resources and no access to the outside world, Anna has only two days to rescue her friends before they are killed or flown out of the country.