Over the car radio, he caught the last item of news: about the Australian mathematician Todd Angle who’d gone missing on a bush walk in Tasmania’s south-west. Dyer was about to turn it off, but the phrase ‘So the whole world can know’ stopped him. A friend had received a letter from Angle two days after he disappeared, beginning with these words written boldly across the top, and containing Angle’s philosophy on reality and a mathematical theory explaining the ideal tax system. ‘I wondered if Todd had committed suicide, but came to the conclusion he had changed a lot since I last saw him.’

Meanwhile, the main news concerned the worsening situation in the Middle East. The American president was promising to ‘dismantle the disastrous deal with Iran’. In response, Iran was ratcheting up the rhetoric. ‘Israel is no longer needed to exist near us.’ Any further provocation, said a spokesman in Tehran, and Iran was prepared to restart its nuclear programme ‘within hours’.

Chapter Seventeen

THIRTY HOURS ON, DYER’S MIND remained congested with everything Marvar had told him. Dyer had lived more on that day than in the last seventeen months; who would have predicted that it would have been so after they ran into each other outside the Oxford University Press?

Yet when Dyer went over it again, he wondered whether Marvar was not being violently overdramatic. Was it possible that no one had laid a finger on Shula, and Marvar’s fears were the product of his disturbed imagination?

The truth has its own smell. There was nothing feigned about Marvar. Even so, Dyer worried that a long period of inactivity had made his own judgement defective. ‘Never put a wet car in a garage,’ his father used to say. ‘It goes rusty.’ Had this happened to Dyer?

He looked forward to a few hours of not having to think about nuclear fusion, for which he had anyway no spontaneous talent; to losing himself, instead, on the coast of sixteenth-century Brazil. The bay below Monte Pascoal. The crump of waves on a high-banked shore. The Portuguese fleet is at anchor.

A cold breeze had blown up, an Oxford breeze, knife sharp, with dead leaves in it, and empty paper cups. Dyer wrapped his scarf tighter. Emerging from Little Clarendon Street, he walked past St Bennett’s, past the Eagle and Child where Tolkien used to meet C. S. Lewis for a beer, past the newly refurbished St Giles’s Café, once upon a time a greasy-spoon where he and his best friend Rougetel escaped from school on Saturday afternoons to eat an illicit egg on toast.