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!

Marooned on Mars is the first episode of the Invasion of the Vorticons trilogy.

In this episode, Keen is exploring Mars when a race of doglike creatures called Vorticons attack his ship, steal four vital components, and scatter them throughout various cities on Mars! No longer capable of leaving Mars, Keen must battle his way through the Vorticon forces to retrieve his ship's parts and return to Earth!

This episode is available on Commander-Keen.com as shareware. Download it today!