On a bright Sunday morning in Hawaii, Japanese planes swoop down and attack the US naval base at Pearl Harbour. America enters the war and Britain no longer stands alone against Hitler. The country can dare to hope again, although a long, hard struggle still clearly lies ahead.

Conditions on the home front remain bleak, and for Scotland Yard detective Frank Merlin, life is as arduous as ever. The carnage wrought by German bombers, the blackout, chronic shortages of food and other essentials, rampant corruption and limited police manpower continue to contribute to London's accelerating wartime crime rate.

In the week of Japan's aggression, Merlin is diverted from his tenacious campaign against London's organised criminal gangs by the violent deaths of two young women in the centre of the city.

The strangled body of one, an unknown teenager, is discovered, mummified, in the rubble of a bombed Victoria office building. The shattered corpse of the other, a famous film actress, is found on the pavement beneath her Mayfair apartment block, an apparent suicide.

Merlin investigates and encounters fraudulent film moguls, dissipated movie stars, mad Satanists and brutal gangsters amongst others as he and his team battle to uncover the connections and search out the truth.