‘Okay,’ I shout. I try to put my foot into my trunks. I can hear the instructor’s voice echoing through the changing room, something about being nearly ready, just waiting for two more. That’s me and Granddad. This is going to be so embarrassing. What person signs up for scuba diving when he can’t even put his head under water? Everyone is going to laugh at me.

‘Granddad,’ I shout. ‘I don’t . . .’

‘I will go on in,’ says Granddad. ‘Here is the key for the locker.’

‘No, Granddad . . .’

The locker key slides under the door.

‘Granddad, wait. I don’t want . . .’ I pull my trunks up and flick the latch. It’s not too late to catch Granddad; he’s bound to want to go to the toilet. I look up and down the changing room for him, but the only person I see is an attendant wearing a red and yellow trackie, mopping the floor. I put my clothes in the locker and run.

‘Oi!’ the attendant shouts and points at a yellow triangle on the floor. ‘Can’t you read? No running. Slippery surface.’

‘I’m sorry,’ I gasp. ‘But I’m looking for my granddad.’

The attendant nods at the footbath.

‘He couldn’t wait.’

‘For the toilet?’

‘No, for the pool. He went through here quicker than Usain Bolt!’

‘What?!’ I turn and splash through the footbath and out into the pool.

Granddad smiles at me as I walk towards him. He’s standing in a line by the pool next to six other people. They all look at me, but I just look at Granddad. He’s wearing a blue polo shirt and trunks that make his legs look as skinny as a chicken’s. He’s way older than anyone else here. They must be thinking that’s a bit weird, but not as weird as his grandson walking along the edge of the pool in red jelly shoes.

‘Ah,’ says the instructor. ‘So this is your grandson, Felix?’

‘Yes.’ Granddad puts his arm around my shoulders. ‘This was all his idea.’

Well, it was Jake’s actually.

‘Great,’ says the instructor. ‘Well, I’m Steve, as most of you know, so would everyone else just like to introduce themselves?’

I lean forward and look along the line. A man about Dad’s age says his name is Andy, a girl a bit older than me says her name is Isobel, and then there are Jon, Karen, Mark, Josh, then . . .

‘Francke!’ barks Granddad, so loudly it echoes around the pool area.

‘Excellent,’ says Steve. ‘We’ll get you all in the water soon, but I just need to run through some important points first.’ He turns towards a flip chart where there’s a picture of a diver with his hands flapping around and bubbles coming out of his mouth. ‘First and most important rule of diving,’ says Steve. ‘Don’t panic!’