Which book/movie/show is the saddest?

‘Bomber’ by Len Deighton.

The story of one mission by the RAF over Germany. Every horror and stupidity of war wrapped into one book.

The first scene is an RAF crew cheering because they have just learned that they will be going up with crews flying older, slower planes. They know the Germans will attack the slower planes first. They are cheering because they know other Englishmen will die. Gets worse from there.