My heart races against the clock. As 17:59 becomes 18:00, it looks like the word ‘Boo.’ Mum says a swear-word and I jump. My swimming lesson starts now but we haven’t even parked the car.

On the radio, the newsreader says an asteroid will narrowly miss Earth tonight. I picture myself riding it, flames shooting behind me, and diving into the pool just in time.

Mum stops the car so suddenly that I jolt forward. ‘Jump out here, Thomas!’

My bag is wedged in the space in front of my seat. I tug while another clock inside my head counts down until Mum explodes. Beside me, she inflates like a balloon. Three, two, one…