Mary Katherine (Amanda Seyfried), or M.K., is a headstrong, spirited teenager who has a strained relationship with her father (Jason Sudeikis). She loses patience with her dad's tales of unseen people who live in the woods, but when she is magically transported to that mythic realm, she gains new perspective. M.K. joins a race of beings known as the Leafmen in their battle to protect their queen (Beyoncé Knowles) from their enemies, evil Mandrake (Christoph Waltz) and his crew of Boggans.