After a shark attack leads to Cleo and Puffer’s eight-legged octopus friend Ollie getting lost in the ocean, a fun-loving manta ray named Crash helps them search the sea to find their lost mate. Along their journey they meet all sorts of fascinating creatures of the deep and learn about each and every one of them during their aquatic adventure..

A constantly picked-on aquarium fish escapes her yacht home, unaware of the dangers that await her in the open ocean. With the help of other misfit sea creatures, she learns not only how to brave the perils of the deep, but how to be true to herself.

When an undersea volcano sends tremors throughout the Atlantic, aquatic creatures come out of hiding. Merchant seamen Joe Ryan and partner Sam Slade harness the most unusual of the lot, a massive beast that looks like a Tyrannosaurus Rex. The enterprising sailors deliver their quarry to a British circus, but it turns out that the animal is a newborn. And, when his much larger mother arrives in London to rescue her son, the city feels her wrath.