Edgar Wallace 
The Face in the Night [EPUB ebook] 

Audrey Bedford, a small town girl, goes to London and is arrested for stealing the Queen of Finland’s necklace. She realizes immediately that her sister is the guilty party, but family loyalty leads her to accept the charge and she does the time rather than implicate her sister. Once released from prison she takes the only job she can find and ends up embroiled in a case of murder, robbery and stolen diamonds. Because of her past she can’t afford to let events unfold as they will, to keep her freedom she must be an active participant in getting to the bottom of this mystery.