It's been years that the underwater monster gives no rest to people. It's sinking submarines, commercial crafts, and even comes out of the sea on land with no one to stop it. You and your submarine are the stronghold for the whole humankind. The craft is equipped with high tech devices and you're the only one to save the world! The very best humans have been racking their brains over the creation of your weapons, and you're chosen as the most experienced, brave and responsible captain on Earth. The underwater world is full of dangers and adventures, you're a stranger here, and the monster is in his home, and not alone. The best defense is an attack! Go ahead, brave captain! Armies of sharks, dolphins, cramp fishes, jelly fishes, crabs, all kinds of fish are waiting for you, and they will use every chance not to let you reach the boss. The enemies are different in the manner of behavior, and it's getting harder with every new level. But you're the only one to defeat this underwater armada. Besides the monsters there's plenty of useful things beneath the sea which will help you reach your not an easy one goal. Don't forget to collect bonuses and the struggle with monsters will become easier then. But the most useful thing is a life buoy; it will let you restock oxygen and equip the craft with different useful tricks. A wonderful world of corals, algae and sea creatures will not leave indifferent even a fastidious gamer, but don't gape at them too much - the monsters will not loose their chance. Welcome to the underwater world, captain!