She reads a story about an unlucky leprechaun. Frankie Sparks thinks it's funny, but it's a fairy tale. After all, everyone knows leprechauns aren't real. Unlike Frankie, her best friend, Maya, is convinced that leprechauns exist. In fact, she tells Frankie that there's a leprechaun living in her backyard! So Frankie decides to build her biggest invention yet: a leprechaun trap! And since her trap will be foolproof, it makes sense that the only reason she doesn't catch them is because those magical creatures are just make-believe. But after a few clues, Frankie begins to have her doubts. Will Frankie and Maya discover this lucky charm is real?