He felt as helpless as a playwright on opening night. He had created the characters, given them their lines, and could see them now on a stage of his making. He could see Isherwood in his chalk-stripe suit and lucky red tie, craving a drink and nibbling on the nail of his left forefinger to relieve the tension. And Chiara seated behind her glossy new receptionist’s desk, with her hair drawn sensibly back and her long legs crossed primly at the ankle. And Sarah, in the black Chanel suit she’d bought at Harrods two weeks earlier, propped serenely on the divan in the upstairs exhibition room, with her eyes on Marguerite Gachet and her thoughts on the monster who would be coming up the lift in two hours’ time. If he could have rewritten anyone’s role, it would have been Sarah’s. It was too late for that now. The curtain was about to rise.

And so all the playwright could do now was pace the drawing room of his safe house and wait for the updates. At 3:04 Mr. Baker’s 747 was seen on low approach to Heathrow Airport, Mr. Baker being their code name for Zizi al-Bakari. At 3:32 came word that Mr. Baker and his entourage had cleared VIP customs. At 3:45 they were seen boarding their limousines, and at 3:52 those same limousines were seen trying to set a land-speed record on the A4. At 4:09 Mr. Baker’s artistic adviser, whom they code-named Marlowe, telephoned Isherwood from the motorcade to say they were running a few minutes behind schedule. That turned out not to be the case, however, because at 4:27 the same motorcade was spotted turning into Duke Street from Piccadilly.

There then followed the first stumble of the afternoon. Thankfully it was Zizi’s and not theirs. It came as the first limousine was attempting to negotiate the narrow passageway from Duke Street into Mason’s Yard. A moment into the exercise the driver determined that the cars were too large to fit through the breach. Sharuki, the advance man, had neglected to take a proper measurement. And so the final message that Gabriel received from the neviot team stated that Mr. Baker, chairman and CEO of Jihad Inc., was getting out of his car and walking to the gallery.