She’s dressed from head to toe in the charity colours, with a ridiculous inflatable hat on her head. She’s short and round and clearly the power behind Harry. Throughout the morning, I watch him glancing to her for approval regularly. She teases him incessantly and he winds her up. They’re obviously mad about each other.

There’s a long, long gap after the first runners go through, shooting past in seconds, following their pacemakers, and the wheelchair athletes, who move so fast that Jess almost misses the whole pack because she’s gone to the loo.

‘So what happens now?’ Jess sits down on a folding chair and shades her eyes, looking up at Andrea.

‘We wait.’ Andrea tapes down a sign that’s come loose.

‘Sounds a bit ominous.’

Andrea nods emphatically. ‘Rained the morning I ran it. I got soaked at the start, then had to run the whole thing in a damp T-shirt. And I lost five toenails.’

‘Yowch.’ Jess pulls a face. ‘How did that happen?’

‘It’s fairly standard – 26.2 miles is a long old way to run.’

‘Can’t believe you did it. That’s amazing,’ Jess says, looking incredibly impressed.

‘I can’t either. It was bloody knackering,’ Andrea says, then gives a snort of laughter. ‘But it seemed a hell of a lot easier than going through six rounds of chemo like he did.’ She nods in the direction of Harry, who is tying balloons full of helium to the side of the charity banner.

‘I love watching the Marathon,’ Jess says. ‘Especially that bit at the beginning where you see everyone’s stories and it makes you cry.’

‘Oh God,’ Becky says as finally she appears. She’s been staying with a friend in Poplar, so she’s on foot, wearing a baseball cap and sunglasses to protect her eyes from the already-bright sunshine. She pinches a couple of jellybabies. ‘Has she told you about how she sits there every year to watch the runners, weeping and eating toast?’

‘Shut up, you,’ Jess says, going pink.

‘True though,’ Becky says. ‘God I am so hungover. I need a saline drip. You haven’t learned to do that yet, have you, Alex?’

‘I don’t have one handy, no,’ I say. ‘And I don’t think the medical tent would be that impressed if you turned up and told them you needed rehydration.’

‘I’m going to go and find some full-fat Coke then. I need to be in full-on cheering mode for the lads from work.’