Or you can lean back in your chair, brace yourself against the wall, get both feet up against the table and shove with all your strength. The edge caught Lesley in the stomach and Reynard across the thighs. Lesley went with the blow – I saw her allow herself to be pushed backwards, finishing her spell as she tipped over. Not an easy thing to do, I can tell you. Reynard screamed with pain and then did a neat little standing jump that left him crouched on the table.

On the sound principle that whatever Lesley had cast I didn’t want to be in front of it, I threw myself diagonally across the table top and while I slid down it I conjured a couple of delayed action fireballs that I call, much to Nightingale’s annoyance, skinny grenades and lobbed them in the Lesley’s general direction. John Woo would have been proud.

I made a half-hearted grab for Reynard but he sort of bounded off the table, through the slot in the wall, and out into the corridor. I let him go – Lesley was my priority now. But before I could roll off the other side, the bloody table lurched and shot straight upwards. I flattened myself as the ceiling came rushing towards me, but there was a bright flash, like a professional standard flash gun, and the table lurched to the left and tipped me off.

I hit something with my shoulder – I think it was Aretha – and smacked face first onto the floor tiles. What with one thing and another, I didn’t think having a rest was a good idea, so I rolled in a random direction and scrambled to my feet. Just in time to see Lesley vault through the slot in the wall and tear after Reynard who was vanishing up a cross corridor marked HARRODS’ TECHNOLOGY. I went after them, but I had my shield up because I really didn’t think this was going to have a happy ending.

It might have been a Wednesday morning, but there were enough punters around to give a working copper conniptions. There are rules about putting the public in danger during a chase – the principle one of which is don’t put members of the public at risk.

‘Police,’ I shouted as a member of the public bounced off my shield. ‘Everybody out.’

Which had the effect of making some people stop, some people reach for their phones, and the rest to carry on shopping regardless.

I shouted again – which at least cleared enough of a hole for me to spot Lesley turning left into the next room. I followed and felt my shield ripple as I veered past a triple-screened games console with built-in racing car controls. There was a smell of burning plastic and I hoped it hadn’t been me.