In which you are a marine engineer. One day you were asked to come at work to repair a broken submarine. So you did whatever you know and took the submarine for a test. You went deep in the sea and the submarine got broken again. That was the moment when you realized that it can't be repaired anymore and now you got trapped in it. Your best chance to escape is by searching the submarine and collecting all the useful items. When you collected everything you need, you can escape from the submarine. Good luck and have fun!