Spectres in the Smoke

It's the austere 1948 world of post-war, black-market-riddled England, and Jethro, the cat burglar and jewel thief, has been pushed out onto the rooftops of London again by Colonel Walsingham of MI5.
And so, forced once again to step out from behind his disguise as a part-time stage-hand in London's West End, Jethro does a creep in Mayfair and sets in motion a tale of dark and deadly dealings that mixes national politics with black magic, orgies of abandon, and blackmail.
Things get even deadlier when he stumbles across a royal cover-up and then uncovers a plot to topple Clement Attlee's Labour Government.
And always ever present, looming in the background, are the twin spectres of the growing communist menace and a rebirth of fascism. There are even rumors the Americans are poking their noses deep into things and that a mysterious OSS agent is roaming around London with his eagle eye set on someone who looks a lot like Jethro.
To top it all, Walsingham comes up with a plan---"in Defence of the Realm"---that calls for Jethro to steal his way into the very heart of English aristocratic circles.
However, Walsingham's behind-the-scenes string pulling also has unintended consequences in London's gangland that result in Jethro finding himself up to his neck again in the never-ending battle between two of London's most notorious gang bosses, Darby Messima and Jack Spot.
And all this is just a precursor to Jethro having to do a very serious bit of burglary at a certain very grand country house, the success or failure of which could mean England saved from going to the dogs or spell curtains for Jethro.