The Nightmare Machine is one of a series of four Spy Kids Learning Adventures. In this episode, the Spy Kids, Carmen and Juni, are called upon by their superiors to rid the world of The Nightmare Machine. It seems that there is a diabolical machine located in the Antarctic that is broadcasting nightmares to all the grown-ups in the world, making sleep rather difficult.

The game unfolds in an animated comic book manner. In order to accomplish the mission, the player guides the Spy Kids through 2 types of challenges. In the first, the game comes with a separate puzzle book (either printed or in PDF format) which can also be downloaded from the publisher's website. The book contains math and logic puzzles. The player will be prompted at various junctures for the answers to certain puzzles in order to advance the storyline.