The Chicago Crime Syndicate were a group lead by Al Capone. They made their only appearance in Night at the Museum: Battle of the Smithsonian, being henchmen to one of the secondary antagonists.
In the Movie
Originally henchmen of Al Capone, they soon joined Kahmunrah when Capone agreed to join forces. They come from a forgotten black and white exhibit in the Smithsonian basement. Although black and white, they later appeared in color.
These guys really love to gamble with each other.
The Chicago Crime Syndicate or Chicago Outfit were a major crime organization based in Chicago. They helped to make Chicago one of America's most dangerous cities of their time, responsible for tragedies like the Saint Valentine Day's Massacure. Al Capone joined them and would eventually rose to their top.
Under Capone, their power and influence increased during the Prohibition Era, during which one of their main illegal activities was bootlegging. This organization became a criminal empire, grossing millions of dollars. Capone had men operating in many U.S states.
Joining the gang, one had to be tough, committed, and extremely loyal. Anyone even suspected of disloyalty were killed by Capone himself. The gang had a series of assassins and gunmen to defend their criminal empire from threats. Their main rival was the North Side Irish Gang.
Police and judges were paid off, jury members were bribed or threatened, and lawmakers were corrupted.