The Hole (1960)

Four cellmates in La Santé prison have been planning a perfect escape plan for a long time. Suddenly, they are assigned a new companion who puts a strain on their strategy; they doubt whether he can be trusted, but finally they tell him the plan and he decides to collaborate. The search for freedom leads them to forge a friendship and talk about their innermost feelings, achieving, in the words of François Truffaut, a masterpiece.