Uptown Saturday Night (1974)

Comedy starring Sidney Poitier and Bill Cosby as two working class friends. One night they decide to go uptown to Zenobia's, a posh gambling hall/nightclub. While having an advantageous winning streak at the crap table, the club is suddenly invaded by a gang of masked men who rob all the customers of their money and their valuables after making them strip down to their underwear.

The next day things look worse when Poitier finds out that a winning lottery ticket is in the wallet that was robbed from him the night before. Together the two friends are determined to find out who was behind the robbery and get the wallet back. They end up employing the services of a crooked detective (Richard Pryor), a poseur politician (Roscoe Lee Browne), and a Godfather-like mob boss (Harry Belafonte) before finally finding the culprit.

Available: Netflix, Amazon