Small-time jewel dealer Howard Chesser (Charles Grodin) is in way over his head when he brokers a deal to purchase and cut a huge stone. When the valuable gem is stolen, Chesser's backer (Trevor Howard) forces him to rob the world's largest diamond exchange. With some inside information and a powerful vacuum, Chesser pulls off the heist but soon finds himself on the run. John Gielgud and Candice Bergen also star in this entertaining crime caper.