 Diamond cutter and confidence man Hans Breel, alias Hugo Werner, owes a large sum to belligerent gambler William Walker. Breel convinces Irene Bedford to let him sell her diamond and cut it to raise money. He sells the diamond to Virginia Trent, but swindles Irene out of her share. Meanwhile his wife, Sarah Werner, is consults Perry Mason for help in recovering funds from her child s trust account that Hans/Hugo has embezzled. Breel smashes Trent s diamond to bits and is later found dead. Sarah is charged with murder, and Perry must defend her.