Intruder Alert + Invaders from Planet X is a software compilation released in 1987 for the ZX Spectrum 48K. Developed by Philip M. Reynolds and published by Compass Software, it combines two interactive experiences. The first part places the player in the cockpit of a space craft, where they must navigate challenges with limited control over the vessel.

The second part, Invaders from Planet X, involves defending against alien invaders. The game features text-based commands and strategic decision-making as players attempt to thwart the extraterrestrial threat. Both parts are set in a science fiction universe, offering unique scenarios to explore.