The new clockface of Westminster Palace shimmers at four and fifty, ignited by twilight like dyes within a blown glass. It is 1859 London, the beating heart of the British Empire slowly waking into modernity. A young earl, Noel Ashford, is called to investigate a curious murder by poison. He makes the connection between this case and the death of his parents, and his life halted by duty and grief begins to move once more. Failure means returning to stagnation, but success may not bring satisfaction.

The victim is the grandfather of his long-time friend, Cedric Hilton, a new-money businessman and birdkeeper. Joining them is Victoria Blaine, a poisons expert with whom Noel had entered into a strange arrangement. Together, they unravel a mystery spanning generations, from tea parties with countesses to the slums of Whitechapel. Both Cedric and Victoria are unscrupulous companions for an earl by every standard of polite society, but such opinions are nothing against the trio’s friendship, loyalty, and love for one another.