The merciless Cronus and his Titan buddies are in hot pursuit of Zeus, Hera, and Poseidon, who plan to travel across the treacherous boiling sea in order to save a fellow Olympian. They have a boat, but they also have a problem: Poseidon can't swim and is terrified of the water (well, really of the creatures that lurk in its depths). The group faces danger after danger as they battle singing sirens, a fishy and ferocious Titan named Oceanus, and people-eating...

The Underworld usually isn't really meant to be a fun place, but tell that to Hades! He loves the dark and the stinky smell of sulfur. However, there is one thing that Hades is not a fan of: dogs. And when Zeus and his fellow Olympians encounter Cerberus, a snarling, three-headed dog, Hades must conquer his fears and tame the hound so everyone can continue into the Underworld and deposit their Titan prisoner, Oceanus, back where he belongs!

Nimbus the pegasus wonders why she cannot be sunny all the time like everyone else, but when she introduces her friend Kelp to her cloud, she finds the unicorn is a very good listener.