Okay, so a long long time ago in a country called the Soviet Union, they built something called a submarine. A submarine is like a big metal tube that goes underwater and people can live inside it for a long time.
Now, this particular submarine was called the K-19. It was a very important submarine because it was supposed to be used to help protect the Soviet Union from other countries who might want to hurt them.
But, there was a problem with the K-19. It was built kind of quickly and some of the parts weren't put together correctly. This is like building a toy really fast and not making sure all the pieces are in the right place.
So, when the K-19 went out into the ocean, some parts started to break down and the people who were inside it started to have problems. It was very scary for them because they were very far away from land and they didn't have a lot of food or water.
The people who were in charge of the K-19 tried to fix the problems but it was very hard. They had to go down into the submarine and try to fix things in very small spaces. It was kind of like playing a game of Operation, but for real and with no light.
Eventually, they were able to fix most of the problems and everyone on the K-19 was okay. But it was a very scary experience for them and they had to go back to the Soviet Union to fix all of the things that were wrong with the submarine.
So, that's the story of the Soviet submarine K-19. It was an important submarine but it had some problems that needed to be fixed.