From Canada's waterlogged wilderness come stories of a twenty-foot lake monster that attacks humans. Freshwater detective Jeremy Wade tries to track down this shadowy predator with a mouth said to resemble a bear-trap.

Jeremy Wade is on the trail of horrifying killers from the depths of time. Fearsome, prehistoric beasts are brought back to life using cutting edge technology and recently unearthed fossils in a quest to find the greatest river monster of all time.