Enter Commander Keen - the alter-ego of an eight year-old genius by the name of William J. "Billy Blaze" Blazkowicz II, grandson of WWII Allied war hero B.J. Blazkowicz of Castle Wolfenstein fame.

When Billy learns that the Earth is in danger, he dons his brother's football helmet and his homemade interstellar spaceship to become Commander Keen - Defender of the Earth!

Aliens Ate My Babysitter! is the final episode of the Commander Keen saga.

Keen's babysitter Molly... is Mortimer McMire's older sister! One day, Keen's parents leave him in her charge. While tinkering in his lab, Keen suddenly hears her scream, and rushes out only to see a Bloob ship leaving our atmosphere... with Molly inside! Now Keen must rush out to stop the Bloobs from eating her, much to his chagrin. Help Keen save Molly and return to Earth to return to more important matters!

Download the demo on Commander-Keen.com.