It was Total War. From 1939 to 1945 the British people were united against tyranny. But the Government, unidealistic, realised that total patriotic unity could not be achieved without some persuasion. An expert in the art of such persuasion was Abram Games.

For Games, a Jewish Socialist artist, the fight against the Nazis meant more than merely defending England's green and pleasant land: his work demonstrates an uncompromising bluntness present in the output of few other wartime poster artists. Having produced a successful poster in 1941 to combat the spread of venereal disease, by August 1942 Games had become the War Office's first official Poster Designer.

Games' posters coerce us into reaction. Initial bafflement turns to intrigue and thence to horror or amusement. Few wartime posters can rival the ghoulish immediacy of Games's exhortation to keep children away from the spare 'blind' munitions left on firing ranges (right). He confuses scale and makes clever use of a classic Surrealist device: photography, tinted, transformed and juxtaposed with the painted or printed image to produce a heightened sense of reality.

The message of the 'Dig for Victory' campaign becomes graphically obvious as a knife and fork are changed into a fork and spade (left). This blurring of fantasy and reality is best exemplified in a series of posters he produced in 1942. A typical example shows 'Your Britain . . . Clean, airy and well planned dwellings. Fight for it now.' In another, a waif in a bombed-out ruin is contrasted with the shining frontage of a planned medical centre: 'Modern medicine means the maintenance of good health and the prevention and early detection of disease. Fight for it now.'

The promise is implicit. Fight for your country and we, the government, will make Britain 'a land fit for heroes'. So they fought and died and Britain won. Games had succeeded. But 50 years on the heroes are still waiting and ultimately this exhibition can teach only one lesson: it pays to advertise.

Imperial War Museum, SE1 (071-416 5000). To 29 Aug

(Photographs omitted)