London 1915 and Great Britain is at war with Germany. Stylish lady detective Miss Isabel Hewitt is involved on the Home Front with the Women's Emergency Corps using her car to help ferry refugees around London. Then someone brutally murders two girls from the Corps in Shoreditch and there are fears the Ripper may be back. Isabel is asked to investigate and she begins a very dangerous mission tracking down a serial killer.

London 1916 and Great Britain is at war with Germany. Stylish lady detective Mss Isabel Hewitt is approached by a wealthy young woman Miss Jen-Eva Howard. She would like Miss Hewitt to look into the murder of her fiance, the journalist Giles Chichester. Isabel agrees, but soon discovers he was an unpleasant sort of man, who wrote contentious articles for his magazine and upset a lot of people. Convinced his death is connected with a case he was working on, Isabel goes undercover to follow up his leads, but the key to unlock the mystery is a white cat. The solution causes Isabel to question her hitherto unshakeable belief in justice.

It is London 1915 and Great Britain is at war with Germany. Stylish lady detective Miss Isabel Hewitt is approached by a young soldier Captain Alex Fraser in the hope of finding his natural mother. He was given away at birth. Isabel agrees to take on his case even though she suspects the mother may be a friend of hers. Her inquiries take her to Brighton where Captain Fraser is staying. But then a girl's body is found on Hove Beach and Isabel is drawn into a shocking murder investigation.

London 1915 and Britain is at war with Germany. Stylish lady detective, Miss Isabel Hewitt, has agreed to play the piano at a fund raising concert. The funds are for a small military hospital where her former manservant, Clarke, works as an orderly. But her rehearsal is interrupted when a Mrs Peveril calls to ask her to investigate the death of her daughter Leah. The police think it is suicide, the mother hopes it is not. Isabel agrees to take on the case, but soon discovers the girl was leading a double life. Is it suicide or murder?