When Miss Pongleton is found murdered on the stairs of Belsize Park station, her fellow-boarders in the Frampton Hotel are not overwhelmed with grief at the death of a tiresome old woman. But they all have their theories about the identity of the murderer, and help to unravel the mystery of who killed the wealthy 'Pongle'.
Mavis Doriel Hay (1894 - 1979) was a novelist of the golden age of British crime fiction. Her three novels - of which Murder Underground was the first - were published in the 1930s and are now very rare. The British Library republished The Santa Klaus Murder in 2013.