She returned the Glock to its holster and her eyes moved back to the ferry. It was closer. Clearer. The movement on the top deck was now plain to see. Movement that seemed unusual.

Levy squinted her eyes and tried to block out the sun with her hand as she focused on the bow of the ferry. She could see what looked like a surge of the passengers. Similar to a tide or a Mexican wave.

The crowd on the deck seemed to be moving as one. First forward. Then left.

‘What the hell’s going on?’ Levy’s question was as much to herself as to anyone else.

‘I’ve no idea.’ Stephen John’s answer was not helpful. Nor was it needed.

Levy’s eyes followed the movement, trying to get ahead of it. To discover what was causing the deck’s strange motion.

Whatever they’re moving towards is what matters, she observed. Not the crowd itself.

The answer came almost immediately. Preceded by an object thrown over the upper deck’s safety rail. A bag, it looked like. From this distance Levy could not be sure.

An instant later and she did not care. The object was followed by something much more compelling. The unmistakable sight of a man, leaping from the ferry to the river below.

‘It’s Penfold!’ Levy shouted the name as the realisation hit her. She was already running as she shouted again

‘GET TO THE RIB!’

The four MIT One officers followed, in the direction of the rigid-inflatable boat that was moored close by. The RIB was there for exactly this situation: an attempted escape at sea.

The firearms officers did not move. This was no accident. Levy had briefed her team on every scenario. Every officer knew what she expected.

The RIB was moving within moments. Piloted by a specialist. Levy pointed him in the right direction, to where Penfold had hit the water.

A seven-minute ferry journey, Stephen John had estimated. It took less than two in the high-performance speedboat.

The RIB reached Penfold quickly. He was still where he had fallen. Levy raised her pistol and aimed it at Penfold’s head.

She quickly realised that the weapon was unnecessary.

Penfold was in no condition to resist arrest. He was barely able to tread water; his head repeatedly went under as he struggled to stay afloat.

The impact with the water had taken a toll. Penfold’s right arm was useless. Broken, it seemed. Or dislocated. Levy could not tell which. Nor did she care. All that mattered was that she had him.

Levy holstered her pistol and turned to the nearest two MIT One officers.

‘Fish him out of there and read the bastard his rights.’

THIRTY-SEVEN

Michael had watched the jury carefully as Keith White presented his evidence. White was the UK’s leading expert in cell-site and mobile-phone data, a field of evidence that had, since the late 1990s, hugely increased in importance.

Mobile phones were everywhere. It was difficult to find a person – old or young – who did not own one. They were the ultimate modern convenience.