Baffling robberies from locked rooms, cunning crimes and mysterious murders...these were all part of the stock-in-trade of Miss Victoria Lincoln, private detective. Called in to investigate the case of the Haunted Gallery, she had occasion to call on the help of Caroline Gerrard, a pupil at her old College. Impressed, she invited the girl to become her assistant after she left College. Thereafter Caroline assisted the detective in a series of bizarre cases that had baffled the police and appeared insoluble — until Victoria Lincoln got to work!