Veronica Daring returns home from an elite finishing school to find her father, Jonathan Daring, an eccentric inventor missing without a trace! The only clue left behind points toward an abandoned amusement park used by her father to test his steam-powered inventions. There she discovers a strange girl named Jules, a fellow inventor who agrees to help Veronica in locating her missing father. Together, Veronica and Jules learn that Jonathan has been kidnapped by a mysterious group of influential persons, who seek to use his latest invention for nefarious purposes. These villains are wealthy and influential and neither Veronica nor Jules can stop them openly. But determined to save her father and holding true to the family creed that technology should be used for the good of all, Veronica assumes the secret identity of Hullabaloo, a goggled crusader who uses wits and science to combat evil and oppose the nefarious conspiracy that has taken her father.