In what clearly was a B picture and no frills other than the comic genius of Red Skelton MGM bid farewell to Skelton with The Great Diamond Robbery. I will say that MGM did give him a good supporting cast.
Red is a foundling who goes by the name of Ambrose C. Park, the "C" stands for Central. He was a baby taken in and raised by Reginald Owen and apprenticed in the jewelry trade. But he's Red Skelton and diamond cutter though he be Owen will not trust him in the cutting of a famous diamond in his possession.
But shyster lawyer James Whitmore gets a hold of the naive and unworldly Skelton who's not as bad as Peter Sellers in Being There, but close enough. He gets George Matthews, Dorothy Stickney, and Cara Williams to play his long lost parents and sister. Later on some higher up on the food chain crooks Kurt Kaszner and Harry Bellaver cut themselves in on the jewel caper they've planned which can be accomplished once they've conned Skelton into cutting the valuable diamond.
More pathos than some of Skelton's more outlandish physical comedy which can be found more on television in which he was spending more time is in The Great Diamond Robbery. Next to Skelton, the women in this film are the most memorable with Stickney especially funny as the old moll as the new Mom.
Skelton fans will appreciate this, but it's not one of his better films.