‘Metropolitan Police,’ she announced, searching her coat for plasticuffs as she advanced. Her pulse jumped again as she reached the nearest recess, staying a few yards off the wall as she gained her first view inside. Empty.

She breathed out and moved towards the next two alcoves, set close together a few yards further on, glancing back at the main street, wondering what was keeping Chris.

She turned back, nearing the second bay, still talking to her unseen target. ‘You’ve done nothing wrong. We just want to ask you some questions.’

No response.

Hawkins covered the last few feet, trying to tread soundlessly as she neared the entrance, not wanting to give her exact position away as she glanced inside the second doorway, also deserted.

The shape broke cover without warning, a streak of movement from the next alcove. But Hawkins was ready, lunging to grab a handful of the watcher’s coat, yanked forwards but not letting go. She hung on as he writhed, managing to get a second hand on his jacket; unable to stop him altogether.

Their shoes ground on the pavement as he tried to pull away, snaking sideways, trying to break Hawkins’ hold.

‘Pack it in!’ she shouted, glad he wasn’t a bigger guy.

He ignored her, kept on wrenching. But she sensed him weakening.

Then he twisted.

Hawkins managed to ease up just in time to stop herself falling against him, but she wasn’t fast enough to stop the elbow that smashed into her cheek, raw shock flashing through her skull. She let go with one hand as her eyes shut automatically, and her thrashing opponent made a fresh bid for freedom, almost hauling her off her feet. Except now she was pissed.

Instead of pulling back harder, she threw her weight after him, lunging in the direction of travel to propel him forwards and down, pivoting as she passed him to yank the watcher off his feet.

He bucked as he fell, letting out a yap of surprise as he slammed into the rear quarter of a van parked near the kerb and went down, face first. Hawkins followed up, dropping her weight on to his spine, driving the air from his lungs, using the diversion to wrestle one cuff over his left wrist and jerk the ligature tight.

‘Hands behind your back,’ she barked, lifting her weight when he complied, securing his arms with the thick cable tie before hauling him to his feet, both of them breathing hard as the watcher slumped against the van. Hawkins made the most of his apparent exhaustion, producing a second pair of cuffs and joining herself to her prisoner.

‘Ma’am!’

She looked around to see Chris lumbering towards them from the far end of the street, his gait suggesting he’d either run a marathon, or not run since school.