The Walther 'Polizei Pistole Kriminal' (PPK) was developed as a compact version of the standard 'Police Pistol' (PP) for concealed use by German plain clothes policemen.
This particular example was lent to Ian Fleming in the late 1950's by the noted author and gun expert Geoffrey Boothroyd. Fleming was so taken with the weapon that not only did he adopt it as the trademark pistol for his character James Bond, but he also named 'Q', Bond's armourer,'Major Boothroyd'