In the seaside town of Dead Man's Cove, two brothers, Johnny and Scotty, spend their summer helping their aunt and cousin run a cafe. While collecting trash on the beach, they stumble upon a friendly sea monster named Sigmund and befriend him, teaching him about human ways. As they navigate their secret friendship, they must also keep Sigmund hidden from the determined Captain Barnabus, who is on a mission to capture a sea monster and prove its existence.
While spending the summer with their cousin Robyn, Johnny and Scott discover ...