In London's affluent Brunswick Gardens, the battle over Charles Darwin's revolutionary theory of evolution intensifies as the respected Reverend Parmenter is boldly challenged by his beautiful assistant, Unity Bellwood - a 'new woman' whose feminism and aggressive Darwinism he finds appalling. When Unity, three months pregnant, tumbles down a staircase to her death, Superintendent Thomas Pitt is certain that one of the three deeply devout men in the house committed murder. Could it have been the Reverend Parmenter? His handsome curate? Or his son, a fervent Roman Catholic? Pitt and his clever wife, Charlotte, will refuse to settle for less than the truth - or less than justice.