When Nico Holland and his friends discover a hidden island in their coastal town, they stumble upon a mysterious houseboat containing a swirling, mist-filled whirlpool called the Darkdeep. Strange and terrifying creatures from their imaginations begin to emerge from this portal, threatening their town of Timbers. The group of friends must work together, facing their own fears and secrets, to understand the Darkdeep's power and stop the chaos before it destroys everything they know.