‘Oh, you know … standing in the middle of the quad, shouting and waving your arms desperately like a chronically spoiled only child who always has to be the center of attention.’ Mary Kate smiled sweetly at me. ‘No offense.’

In the end, Mary Kate had threatened to ditch the flash mob for a chance at romance and Nutella with the French Club’s Crêpes and Conversation afternoon, and we had come to a compromise.

‘Mary Kate’s gonna film us,’ I explained. ‘We’re gonna upload it afterward for the whole world to see!’

‘You are?’ Claudia whirled around. She hurried over to Mary Kate. ‘Upload on what? Instagram? YouTube? Wait, can you link my channel on there?’

After I had unzipped my backpack, distributed copies of the play to everyone and rearranged Sarah and Sophia, who had switched places again, it was my turn to boss Mary Kate around.

‘Can you see all of us?’ I called to her. ‘Make sure you can see all of us. Wait – what should we call the video? Pop-up Vagina Monologues Shocks Catholic School? Rad Feminist Flash Mob Rocks Conservative Campus?’

Mary Kate was holding my phone uneasily at a distance from her body, like it might secretly be a Transformer that would spontaneously erupt into a tractor-trailer with python teeth. She looked around the quad anxiously. ‘Let’s just get this over with,’ she urged me. ‘We’ll figure out the name after.’

‘Right,’ I agreed. ‘I’m sure we’ll have an OMG moment that will make it go viral. We’ll name the video after that.’

Clearing my throat, I cracked the spine on my second-hand Monologues and found one of my favorite passages. I told everyone the page and they turned to it, too. Maybe Mary Kate was right about my only-child Napoleon complex or whatever she’d said, but I had a feeling this was going to be great.

‘THE CLITORIS!’ I boomed.

Then I heard it.

It started with the low bum-bum-bum, which at first I thought was my own heart racing with adrenaline and excitement. But no, it grew louder, shaking the quad like an earthquake – a bass drum. Then the rat-a-tat-tat of the snare drum, and a big crash of cymbals set off a sweeping explosion of music – horns blaring, flutes and piccolos twittering …

Then I saw it.

The sun glinted off big brass tubas and enormous white drums – a whole green army in green hats with gold tassels, marching in unison, a hundred pairs of shining shoes pounding the grass of the quad: the St Mary’s Marching Band.

‘They’re heading straight towards us!’ Sarah or Sophia exclaimed.

‘I’m turning the camera off!’ Mary Kate called out to me.

‘No!’ I protested, waving my arms. ‘Keep filming!’

‘I CAN’T EVEN HEAR YOU!’ she shouted back.