Artemis is an innocent 10-year-old girl with a caring personality. She enjoys her simple, quiet life with her best friend, Edmund, both of whom live in an orphanage since life found them both parentless.
But one night, Artemis hears a woman crying from her open window. The girl's concern prompts her to wake Edmund and drag him through the cold, dark woods in search of the woman, but what they find shocks them.
The children suddenly find themselves in a strange, eerie circus, where they get stuck playing sinister games and solving difficult puzzles trying to escape. They are told if they cannot escape by midnight, they'll be trapped even longer; far too long for two children who just want to go home!
Desperate to get free, the children do all they can to win. But as time runs short, the tasks become nearly impossible, and Artemis and Edmund realize their own lives are now at stake.