You're trapped! Your disabled nuclear submarine, resting perilously on an undersea ledge, has begun taking on water. With time running out for you and your crew – and with your onboard torpedoes shaken loose by an eerie current from deep under the sea floor – it's up to you alone whether you sink or swim!
The objective of Airlock is to retrieve the hatch keys and make your way to the next level before your compartment floods. But at the same time you must avoid the torpedoes that have been shaken loose and which, when they cross your path, rob you of precious time.