For hundreds of years the Pact of Protection has held in the town of Brigus, NL, and the seaside fishing town has guarded an ancient and dangerous knowledge. But when a business tycoon begins blasting rock for a tunnel, it's more than rock that is blown apart: the pact itself is weakened and bits of the secret begin to slip out. In their search for hidden pirate treasure, twelve-year-old Alistair and his friends Ben and Sadie stumble into the middle of this mystery. The more they learn about the pact, the more the shrieking song, the unexplained leaks in fishing vessels, and the mystery ship in the harbour begin to make sense.