We had a good view of the Renault as it accelerated past us towards the far side of the garage. And an equally good look at the bonnet when it exploded in a ball of fire. Exactly the way cars in films do, and cars in real life don’t. It scraped forward for a couple of metres before grinding to a stop. Oily smoke poured from the ruined front of the car and, had there been any water left, that would have been a good time for the sprinklers to activate.

Lesley kicked and twisted, but I think me and Guleed had both decided that our operational priority was arresting her which, unlike everything else going on around us, seemed within our performance envelope.

The back of the Renault blew open of its own accord and a couple of storage crates, the same make as the ones back at The Chestnut Tree, bounced out onto the wet tarmac. Lesley made a lunge forward and then recoiled as Guleed sprayed her in the face with her CS aerosol.

‘Sahra!’ she spluttered.

In the still underground air the smoke was quickly rolling over our heads. According to Frank Caffrey, about a third of fire deaths are down to smoke inhalation and he’s a professional so he should know. I wanted out of that basement. Fortunately, so did Guleed.

‘The stairwell,’ she shouted and we each kept one hand on Lesley as we crawled towards the atrium with the lifts and stairs. Also, I was thinking of those nice thick fire doors and the strong possibility that Stephanopoulos would be available nearby for tea, sympathy and first aid.

Lesley didn’t co-operate.

She somehow managed to roll herself sideways, right over my back, wrenching the speedcuffs out of my left hand and smashing her elbow into the side of my face so that my skull smacked the ground. I really wasn’t any good to man or police officer for what seemed like half an hour, but was probably more like ten seconds. The smoke had boiled down to ground level by then and I came to with Lesley gone and Guleed trying to drag me towards where she hoped the stairs were.

I couldn’t see more than half a metre and every breath burnt the back of my throat. I was beginning to get seriously worried when I smelt dust and sandalwood and what might have been the hot wind off the desert, or possibly just the car burning a few metres away. Then the smoke blew away like the parting of the Red Sea and Lady Helena walked calmly past us down a lengthening corridor of clear air towards the Renault. She lifted her right hand and made a clenching gesture and the fire that engulfed the engine block snuffed out.

Now that was a spell I definitely wanted to learn.