The Victory Movement, led by Sir Arthur Vane, is a political organisation that has fascist policies such as keep Britain white. It is contesting the next election, which has caused violent protests. When a bomb is exploded outside Vane's apartment Gideon is in charge of the investigation. The obvious suspects are his political opponents. A young woman is a possible witness but she has to be found and convinced to say what she knows. Another bomb makes the case more urgent.
—jem