“Tales of the Riverbank” follows the adventure of three companions—Hammy Hamster, Roderick Rat, and GP the Guinea Pig—who are carried away by a fierce storm and set off on a grand quest to find their missing homes. Their expedition, filled with humorous mishaps and thrilling perils, takes a more perilous turn when they learn that the entire riverbank is endangered by a factory producing waffles, marmalade, and doughnuts. This factory, run by the villainous Fat Cats, is contaminating the environment with ever more hazardous pollutants, known as the Big Dirt.