Space Quest I: The Sarien Encounter

Roger is a member of the cleaning crew onboard the scientific spaceship "Arcada", which holds a powerful experimental device called the "Star Generator". Roger emerges from an on-duty nap in a broom closet to find the ship has been taken over by the sinister Sariens. He must make his escape, survive a crash-landing on the desert planet Kerona, and ultimately sneak aboard the Sarien starship Deltaur to stop the vicious aliens from using the Star Generator against Roger's home planet of Xenon.