The Penny Nichols series consists of four titles: 1. Penny Nichols Finds
a Clue (1936) 2. Penny Nichols and the Mystery of the Lost Key (1936) 3.
Penny Nichols and the Black Imp (1936) 4. Penny Nichols and the Knob
Hill Mystery (1939) Penny Nichols is the daughter of Christopher
Nichols, an eminent detective. Penny's dad often disregards her ideas,
but time and again she is proved right and he has to recognise that she
is also a good detective. Penny is often accompanied in her adventures
by her best friend, Susan Altman. These books have fabulous plots and
are page turners for children of any age. Enjoy!