During World War I a German U-boat sinks a British ship, taking the survivors captive. After several mutinies and wrong turns, the submarine emerges on the shores of the unknown island of Caprona, deep within the perilous Bermuda Triangle, where dinosaurs and Neanderthals live in a world untouched by time. Now they must fight to survive in an arcane world, where the many dangers help the war-time enemies to forget their now-trivial differences and fight together for their ultimate survival.