He pointed at the guy on the ground, who had put his phone away. ‘Him. Or him crazy brother, Kyle.’

My grip relaxed slightly as I felt Ali’s body tremble and realised he was crying.

Ali must’ve sensed my momentary loss of concentration. With one almighty yank, he took a flying leap, and launched himself past Dan towards the doorway from the lounge into the corridor. Dan lost his balance and fell on his side. Moments later, I heard the front door of the building bang shut. Before I knew it, the wiry body was up from the floor. The youth plunged after Ali, out of the squat, and began sprinting along the corridor towards the exit.

‘Bugger,’ Dan yelled, as he scrambled to his feet. ‘We well and truly screwed that up.’ He turned to me, his eyes blazing. ‘Right. Time to call it in. Let’s get this shithole cleared before any more of these kids nick off. They need to be in foster homes where they’re safe and we can keep an eye on them.’ He took out his mobile.

Dan was right. We’d assumed we were visiting a home and had been foolish to go inside without back-up. I’d allowed impatience to cloud my judgement. ‘I’d better alert Jackie. She’s going to be furious.’

‘Good idea. I’ll start putting calls out about Ali and the other boy. Somehow I don’t think Ali was joking about Kyle.’

Through the dim light of the squat, I caught Dan’s expression and knew he felt as scared for Ali as I did.

Maya, 8.30 p.m.

Maya, 8.30 p.m.

As we left the estate, the sequence of events at the squat were playing on a constant loop in my mind. I couldn’t escape the fact we’d cocked up. Ali had run off. He seemed sure that someone called Kyle was going to kill him, and that meant we’d exposed him to even greater danger. What the hell were these kids mixed up in? I was sure about one thing: I had to find Ali.

And that meant going looking for him.

From the squat, I drove straight to Brick Lane.

At night, it always took on a different quality from the daytime. This evening, the brightly coloured neon strips seemed to jump out at me from the shops. Vandalised street lights plunged me in and out of darkness, and shadows lurked beside every vehicle and wheelie bin. Each street corner was filled with menace. I kept my eyes peeled for anyone of Ali’s age, scouring doorways and alleys for a scrawny kid with black hair and white trainers.