It is a beautiful made movie, great script, great acting, great direction, great story.
Henry Fonda is brilliant as the man who stands up to the other 11. IMDB says that Fonda regarded it as one of the 3 best movies he ever made.
The way the story evolves is a joy. People's motivations, prejudices, failings, weaknesses, etc. are revealed one by one. The movie has the feeling of a play - the majority of the action takes place in the jury room. There is an elegant simplicity about it.
As I write it is at position 6 on the IMDB Top 250 list.
My rating: 9/10
Here is a still which shows most of the cast:
