It's summertime in Columbia, Missouri. The college students have all gone home and Kirsten (Hari Leigh), a blissfully irresponsible register jerk, reigns as the clown princess of the downtown bar scene. Kirsten works ten hours a week at Shakespeare's Pizza and is entirely satisfied with her humble but comfortable world, although she is despised by her long-suffering roommate (Amy Seimetz) and her best friend (Josh Fadem) has come to tire of shepherding Kirsten's drunken antics. While reluctantly reconnecting with an eccentric childhood friend (Susan Burke) who has recently moved to town, an ill-fated nitrous oxide bender unexpectedly forces Kirsten's first baby steps into adulthood.
A decade after his heroic defeat of the monstrous Kraken, Perseus-the demigod son of Zeus-is attempting to live a quieter life as a village fisherman and the sole parent to his 10-year old son, Helius.
When an evil spirit known as Pitch lays down the gauntlet to take over the world, the immortal Guardians must join forces for the first time to protect the hopes, beliefs and imagination of children all over the world.