Matt Simmons has two weeks left of summer before starting grade six. He wants to enjoy that time with his best friends, Danny and Emma, but has to include his younger cousin Adam who is visiting. Trapped on a sandbar in the middle of the night, Matt and Adam see a ghostly, burning schooner before a silent old man rescues them. Matt is determined to unravel the mystery and reluctantly lets Adam join in. With Danny and Emma, they visit Danny's grandpa, a retired sea captain. He warns them to leave the ghosts and mysteries of the sea alone, but the four friends ignore him. Setting out on a midnight boat trip to find the phantom ship, even little Adam proves a useful part of the team. But how dangerous is the ship, and who else is lurking in the waters of the Northumberland Strait?