An ace at extinguishing oil-field blazes, John R. Ingram now battles a personal inferno of his own. A fugitive after a false robbery conviction, the now-respectable Oklahoma family man sees his life and livelihood go up in smoke after a deceitful ex-shipmate reenters his life, reveals his secret past, swindles him out of his new oil venture and causes him to be sent back to the living hell of the Georgia chain gang, where the guard from whom he escaped the first time is waiting for him. Pushed to the breaking point, Edward G. Robinson gives a powder-keg performance as Ingram, the wronged man seeking righteous justice in Blackmail, a nifty revenge thriller outfitted with class (Ruth Hussey as John's stalwart wife) and grit (Gene Lockhart in a rare turn as a honey-voiced conniver). It all comes to an incendiary finale as Robinson, driven to clear himself, takes on a face of fire confronting loathsome Lockhart at an oil-well conflagration. There you'll also feel the burn of a consummate actor igniting genre material into flaming-good entertainment.