Sonny - the bank robber trying to get money for his male lover's sex-change operation - is a far cry from the cold-eyed Michael Corleone in The Godfather, but the character demonstrated Pacino's incredible range and capacity for explosive rage. Iconic director Sidney Lumet's second film with Pacino after the similarly incendiary Serpico is an acting tour-de-force as the robbery goes horribly wrong and Sonny and his gang face down the NYPD.