Imagine you were in a small, metal, airtight compartment in a submarine stuck on the bottom of the ocean. All around, you can hear metal groaning, rushing water and knocks on the hull from the rescue crew trying to free you. At the same time, you and the men around you are perfectly silent, forbidden from talking so that you don’t run out of air before the rescuers get to you. This is exactly what happened to the crew of a military sub in 1953, and this is their horrifying story.