Barker, a deranged, embittered old lag and his young accomplice Stacey - whom he disguises as a female hostage - dig in on a warehouse roof, pointing their machine-gun at a hospital ward and threatening to kill the patients unless they are given a million pounds. Bodie and ace climber Murphy scale a factory chimney to get height on them but almost scupper the operation. Doyle, however, after a visit to Stacey's girlfriend, has a better plan.