British weapons are being smuggled to trouble-spots abroad, creating a dangerous political situation. Steed arranges for Cathy, armed with 20 per cent of the shares, to join the board of Anderson's Small Arms Ltd, a firm whose chairman has just been killed, and which is frightning a take-over bid from Calder, a tycoon. Cathy meets other board-members, including a Brigadier, and the super-efficient Miss Ellis.