A metallic crash shatters the early morning silence of a local Lake Erie marsh, and teenage brothers Luke and Isaac see an enormous creature rush back into the lake from a nearby channel. It was bigger than anything they'd ever imagined living in the lake, and it wanted into the marsh. Was it a fish? A whale? Or something straight out of legend: the Lake Erie Monster? A quest ensues which takes them to the Erie Islands and a park ranger who thinks the whole thing is a hoax. In the end they learn what the creature is and what it wants, but they're left with a secret they must carry for the rest of their lives.