As the plane bumped along the potholed runway he estimated that it would be at least an hour before he cleared customs and was able to convert some sterling into the local currency. In fact, it took an hour and fourteen minutes, despite his only having an overnight bag and exchanging ten pounds for twenty-five rubles. He then had to join the end of a long taxi queue, because the Russians hadn’t quite got the hang of free enterprise.

“The corner of Nevsky Prospekt and Bolshaya Morskaya Street,” he instructed the driver in his native tongue, hoping he would know where it was. All those hours learning Russian, when in truth he would only need a few well-honed phrases, as he intended to be on his way back to England in a few hours, mission completed, as his old commanding officer would say.

During the drive into the city they passed the Yusupov Palace, when Harry’s thoughts turned to Rasputin. The arch manipulator might have enjoyed his little subterfuge. Harry only hoped he wouldn’t end up being poisoned, wrapped in a carpet and then dropped through an ice-hole in the Malaya Nevka river. Harry realized that if he was going to be back at the airport in time to board the 21:10 to Heathrow, he would only have twenty or thirty minutes to spare. But that should be more than enough.

The taxi driver stopped outside an antiquarian bookshop and pointed to the meter. Harry took out a five-ruble note and handed it to him.

“I don’t expect to be long, so would you be kind enough to wait?”

The driver pocketed the note and gave him a curt nod.

The moment Harry stepped inside the shop, he could see why Mrs. Babakov had chosen this particular establishment in which to secrete her treasure. It was almost as if they didn’t want to sell anything. An elderly woman was seated behind the counter, her head in a book. Harry smiled at her, but she didn’t even look up when the bell rang above the door.

He took a couple of books down from a nearby shelf and pretended to peruse them as he edged his way slowly to the back of the shop, his heart beating a little faster with each step he took. Would it still be there? Had someone already bought it, only to discover when they got home that they’d got the wrong book? Had another customer captured the prize and destroyed Uncle Joe for fear they might be caught with it? He could think of a dozen reasons why the three-thousand-mile round trip could turn out to be a wasted journey. But for the moment, hope still triumphed over expectation.