The Big Caper (1957)
Crime thriller about a broke con man who pitches the idea of a small town bank heist to his well-to-do partner in crime. His partner takes him up on his idea and goes to work putting together a motley crew of dysfunctional criminals to join in and help them pull off the heist. The film ends with a sappy whimper that made me groan in disbelief but up until the last couple of minutes, it was cooking.