Billy Blaze is an eight-year old genius has created a starship from old soup cans and decided to take it for a trip when his parents were out of town and his babysitter fell asleep. Taking his brother's football helmet, he becomes Commander Keen, defender of Earth.
Aliens from the planet Vorticon VI find out about the eight year-old genius and plan his destruction. While Keen is out exploring the mountains of Mars, the Vorticons steal vital parts of his ship and take them to distant Martian cities! Can Keen recover all the pieces of his ship and repel the Vorticon invasion? Will he make it back before his parents get home?
When NASA landed the Viking Lander on Mars, little did they know it caused a major political upheaval. It actually landed on the Martian King, which freed the Yorps from their enslavement which made the Gargs extremely angry.
Commander Keen Episode I: Marooned on Mars is the first game in the Commander Keen series. The game was born out of a plan to port Super Mario Bros. to the PC after John Carmack managed to create smooth horizontal scrolling on the platform1 - which Nintendo politely declined (despite being impressed) as they wanted the Mario series to stay exclusive to their consoles. The game (and subsequent sequels) pioneers the shareware model of distribution and are notably the first games developed by ID Software who notably went on to develop Wolfenstein 3D, the DOOM series and Quake series.