A movement and voices at the entrance make us all turn to look. A man is coming out, surrounded by security people who are so freaking enormous that all I can see is a flash of his hair.

‘Move,’ Hoche barks at her camera dude, and she click-clacks towards the doors, barging into security and trying to push her way through. There’s a shout from the guards and she stumbles and falls to the ground at their feet. Suddenly what must be every police officer in the university and surrounding area appear from between buildings and through all the entrances and exits, and come sprinting towards her. They are saying something as they run that I can’t make out. I don’t wait to find out what it is. 65

‘This is our chance,’ I say, and Kat and Karim follow as I run around the side of the building.

‘There,’ I say, pointing to a fire exit about two thirds of the way around the Cake.

‘But they only open from the inside,’ Karim says. ‘Unless you have secret Hulk powers, I don’t see how we’re getting in that exit.’

‘Leave that to Kat,’ I say. ‘Katja, will you do the honours?’

‘On it.’ She ties her hair back in a ponytail as she runs to the wall next to the fire exit and looks up. Two floors above is a window that must have had all of its glass blown out in the explosion. Kat pushes off from the floor and grabs on to one of the white metal poles that form the building’s exterior structure. It’s an impressive jump – she must get about two metres of air. She swings from one arm for a second, then pulls herself up so that she has another handhold and her feet are on the wall. Then she darts up the building like she’s never done anything easier in her life.

‘Oh, I see.’ Karim gazes up at her. ‘You don’t need secret Hulk powers, because Kat has secret Spider-Man powers.’

I grin as Kat disappears through the open 66 window. We hang back against the fire exit door, keeping a look out for any police or security, but Miss Hoche’s unintended distraction was a good one, and a few minutes later Kat opens the door.

We’re in a dim, narrow corridor that looks like it doesn’t get used very often. There’s a cleaning cart parked against one wall, and a few broken chairs piled up next to it. Kat leads us forward and through a door to the bottom of a stairwell.

‘Where will your mum be?’ I ask, as we start up the stairs.