But she hadn’t thought about the next day. Or how the urge to read the post might strengthen overnight rather than fade.

She pushes open the front door of her flat and heads straight to the bathroom. Once the shower is running hot, she climbs into the bathtub and lets the water rain down over her body. She closes her eyes and lifts her head into the path of its flow. She doesn’t really believe in God, or karma or destiny. But there is something fateful about Beth living on the street where she works. As though it’s a sign, a kick up the arse to be braver. She is 34 now, Kat reminds herself, not the naive 16-year-old unable to read signals anymore.

And anyway, all she wants to do is read an article about Beth on a social media website. Hundreds of other people will have already done that, so why not her?

It sounds so simple when she thinks of it like that.

Kat doesn’t bother with her usual skincare regime, just roughly dries herself, then finds a pair of joggers and a hoodie screwed up at the bottom of her bed. Her dad wasn’t one for house rules, so Kat’s style of tidying hasn’t matured much since she was a teenager. She pulls her laptop off the floor and places it carefully in the middle of her bed.

But suddenly she’s not sure. Is she fooling herself? Is this the first step down a dangerous path, like an ex-smoker convincing himself one cigarette can’t hurt?

She retreats to the kitchen and pulls a bottle of pale ale out of the fridge, her favourite craft beer that’s brewed locally in Brixton. She grabs a fish slice from the drawer, lines its sharp end up against the bottle and flicks the cap off. She smiles as the shiny yellow disc sails up, then falls onto the laminate work surface with a clink. It’s a trick her dad taught her on her eighteenth birthday, and it became part of the routine every time they had a drink together. Tonight, it’s enough to give her the confidence to return to her bedroom, and the glowing laptop.