When you start the adventure, the spaceship pilot is hurt and unconscious, and your mission is to save him. The spaceship won't be able to stand the pressure of the water, so you have to act quickly and stop both the pilot and yourself, the rescue bot, from dying.
To solve this problem you have to use everything you have at hand. You can pick up things like the astronaut's helmet and a simple cup, and try to use them with other items. Some of the puzzles can be complicated, although generally the difficult thing is to find them in the middle of such a dark space.
Beacon is a traditional graphic adventure. Although it's really short (just 15 minutes), it has interesting puzzles and spectacular graphics. The ambiance is also really great.