They had to wrap their arms across their mouths against the smoke. When they entered the short stone tunnel, there was a noise like the sound the roof of the chapel had made just before it began to cave in. For a moment Fleet was sure the entire archway was going to fall on their heads. But they made it through, and when they emerged into the central courtyard, the air was immediately clearer. Even the heat was less intense.

The eye of the storm, Fleet thought to himself grimly.

He looked around – and saw a body on the ground beside the fountain.

He thought at first that it was Richardson. Either Fleet had been wrong about what Isaac meant to do, or Richardson had forced a change of plan.

But as Fleet rushed to the man’s side, he realised it was one of the bodyguards he’d seen hunting for Richardson in the grounds. The man’s suit jacket was heavy with blood, but he was alive.

‘That way,’ the bodyguard growled, as Fleet bent close. ‘They went … that way.’ One hand was holding his stomach. The other pointed across the quad.

Fleet helped Bevan to get the man sitting up. He looked the way they’d come, and saw flames were already spouting from the windows above the archway. The bodyguard’s colleague had appeared on the other side of the tunnel, his finger pressed to his earpiece, but Fleet waved him back. Bevan was radioing for medical assistance, but it was clear the fire would be all around them by the time an ambulance crew arrived.

‘Help me get him to his feet,’ Fleet instructed.

The bodyguard roared in pain as Fleet and Bevan hauled him upright, but the fact that he was able to scream at all told Fleet there was still some strength left in him.

‘Go,’ said Bevan. ‘I’ve got him.’

Fleet looked across doubtfully, but Bevan nodded his insistence. The bodyguard was clutching the stab wound in his belly, blood leaking through his fingers, but he was able to support most of his own weight.

The bodyguard raised his head. ‘If you hurry, you’ll … catch them,’ he said through his grimace.

Fleet pointed to a door in the north-west corner of the quad. ‘Go that way. Head right once you get inside, and don’t stop. The corridor will take you to the entrance hall.’

Bevan started off, the bodyguard’s arm slung around his shoulders. Fleet watched to make sure they could manage, then turned the way the bodyguard had directed him. There was a small wooden door hanging open in a wall that jutted into the quad. Fleet’s gaze drifted up, and he saw the clock tower looming overhead.

He swore inwardly, realising his instincts about Isaac’s intentions had been right.