Suddenly they weren’t all looking at Matthew. Suddenly some of them were looking at her. She went cold with the knowledge that something bad was about to happen and it was about to happen to her. Fear twisted a knot in her stomach. Her blood turned to ice-water. She had shoulder-length hair pulled tightly back into a plait. How easy would it be to hack that off? She took a step backwards and banged her head painfully on something metallic. Someone laughed. Which turned out to be a mistake because the object she’d just banged her head on was a fire extinguisher.

She gave no thought to any possible consequences, ripping it off the wall. She’d done this in training. It was easy, they’d said. Just pull the ring and point. She pulled the ring and pointed.

The extinguisher was designed primarily for extinguishing fires, but self-defence came a close second and it performed well, covering everything in a thick, fire-suppressing, dirty-grey foam, but not for anything like long enough, and as the stream lost pressure and died away, it dawned on Jane that she possibly might have made things considerably worse.

Five or six foam-covered figures were looking for a fight and now she’d given them a reason.

‘Jane. Over here with me.’

Still clutching the extinguisher, partly for moral support and partly because it might come in useful, she edged along the wall to stand alongside Matthew.

Both sides drew breath . . .

Someone walked around the corner and stopped dead. ‘What the hell is going on here?’

They had no idea who had spoken but that was unimportant. Jane dropped the fire extinguisher with a clang, Matthew grabbed his bag and the two of them fled.

A solitary Time Police corridor, just like St Mary’s, is now distinguished by blobs of hardened grey foam making interesting patterns up the walls.

There were repercussions, of course.

Ellis was not amused. ‘Farrell, what the hell have you done to your hair?’

‘It was me,’ said Jane, blushing. ‘You’re always telling him to get it cut so I tried to tidy it up. I’m not very good.’

And indeed, they had spent twenty minutes in Matthew’s room trying to tidy up his semi-bald patches. The result was regrettable.

‘I don’t think I’ve helped,’ she’d said eventually, staring at him in the mirror. ‘You now look as if you have a dreadful scalp condition.’

‘Well, thank you, anyway. I’m very grateful. Cool move with the extinguisher.’

‘I’m going to be in trouble over that, aren’t I?’

He regarded her steadily for a moment – his usual precursor to saying something important. ‘Jane, you should speak up for yourself more. This is the Time Police. They’re not deep thinkers and most of them are the sort of people who equate quietness with stupidity.’

‘You don’t say much yourself.’