Ben Aaronovitch & Andrew Cartmel 
Rivers of London [PDF ebook] 
Action At A Distance #3

October 1957. Thomas Nightingale, Chief Inspector and wizarding legend, reunited with an old friend he met during the Second World War. The friend, Angus Strallen, was in pursuit of a serial killer, Professor Uwe Fischer, a Luftwaffe pilot who settled in Cumberland after the war to work in a factory. Fischer had been targeting women of different cultures which led him – and Strallen – to the cultural melting pot of London. Seemingly always one step ahead of the Metropolitan Police, Fischer kept evading capture, putting his own magical powers and good political relations to use.But as the German scientists read American comic books in his hotel room, Strallen’s partner in crime (and romance), Dr. Jacqueline Frye, acquired a very helpful package from Fischer’s home in Cumberland which was soon on its way to London: a scarf. Paired with the powerful nose of a bloodhound named Hesperus, Nightingale and Strallen’s hunt for Fischer is afoot…