The turquoise baseball cap turns … and it’s not Sage Seymour. It’s some girl with a pointy nose and brown hair who just gives me a blank look and ups her pace. She’s not even wearing a TEAM SAGE cap, either, just a plain turquoise one. I’m so disconcerted I stop dead, and nearly get knocked over by a horde of runners.

‘Jesus!’

‘Out of the way!’

‘One-eight-four, what are you doing?’

Hastily I move to one side and try to catch my breath. OK, so that wasn’t Sage. But never mind. She’ll be here somewhere. I just have to keep my eyes open for turquoise … turquoise … Yes! Over there!

With a fresh surge of adrenalin I plunge into the race again and chase after another turquoise baseball cap. But as I draw near, I can see already that it’s not Sage. It’s not even a girl. It’s a skinny, Italian-looking guy.

Bloody hell. Panting hard, I head to a water station and take a sip of water, still desperately scanning the crowd of runners, refusing to give up. So I’ve had two near-misses. Never mind. I’ll find her. I will. Wait, there’s a flash of turquoise up ahead. That must be her …

An hour later, I feel like I’ve moved into a parallel universe. Is this ‘The Zone’? It feels more like hell. My lungs are pumping like pistons; my face is sweaty; I have blisters on both feet; I want to die … and yet still I’m moving. It’s as if some magic force is keeping me going. I keep seeing turquoise baseball caps in the crowd. I keep chasing them. I’ve approached one blonde girl four times now. But none of them is Sage. Where is she? Where is she?

And where are these bloody endorphins? I’ve been running for ages and haven’t had a single one. It’s all lies. Nor have I seen a single Hollywood landmark. Have we even passed any?

Oh God, I have to drink some water. I head to the next water stand, decorated with helium balloons. I grab one paper cup and pour the water over my head, then gulp at a second. There’s a crowd of cheerleaders in red costumes doing a routine nearby, and I look at them enviously. Where do they get all that energy from? Maybe they have special springy cheerleaders’ boots. Maybe if I had glittery pom-poms to shake, I’d run faster.

‘Becky! Over here! Are you all right?’ I straighten up, panting, and look around in a daze. Then I spot Luke on the other side of the barricade. He’s holding a Ten Miler flag and gazing at me in alarm. ‘Are you all right?’ he repeats.

‘Fine.’ My voice comes out rasping. ‘All good.’

‘I thought I’d come along to support you.’ He eyes me in amazement as I stagger towards him. ‘You’re making incredibly good time. I didn’t realize you were so fit!’

‘Oh.’ I wipe my sweaty face. ‘Right.’ I hadn’t even thought about how quickly I was going. The whole race has been a blur of chasing turquoise baseball caps.