When a deadly vine shows up in his kingdom and gravely injures the king, frog prince Chirp and her friends--a golden retriever named June, a cat named Rose (June's romantic interest), and a snakelike creature named Goro who has a boyfriend--band together as the Dungeon Critters to investigate. Clues lead to Chirp's nemesis, Baron Foxworthy, so the group goes undercover at a ball the Baron is hosting to gather evidence that will implicate him in the crime and save the king.
