Nevis is feeling queasy, though she knows it’s only nerves. They are in Clifton now, the tyres of the Prius tocking wildly across granite setts. True to his word, Farok is driving like a man whose wife is about to give birth in the back. Or a man trying to prevent a death. She checks the time remaining on Google Maps and notices the missed calls and messages from Honor. She will have to call or text later. For now, it is more important to prepare herself for whatever she is about to face. Why has Satnam asked for her? Has she kept something from her? What can be so bad that she has never mentioned it to Nevis? Weren’t they supposed to be best friends? What can she be wanting to say that Nevis doesn’t already know? Why did Nevis never think to press her about the weight loss? Why didn’t she probe when Satnam talked about leaving uni? Why did she allow herself to be soothed by Satnam when she said her tears were PMT? She sees now that these things might have been cries for help. Why didn’t she see it then?

I’m stupid, she thinks. I’m a bad friend.

At last the Clifton Suspension Bridge looms up ahead, dimly lit by a thin moon. The lights are customarily switched off at midnight and it is now gone half past. The journey has taken one minute fifteen seconds less than the prediction on Google Maps, but it’s been the longest journey of Nevis’s life.

And there is still further to go.

Directly ahead on either side of the slipway onto the bridge stand the two toll houses, each illuminated by a night light, and beyond them the looming mass of the first tower dimly lit by the moon. No one is visible. Where are the toll house attendants? She’d read somewhere that after midnight, when the lights on the bridge switch off, body heat cameras are able to detect anyone climbing the suicide barrier. Perhaps the attendants have picked up Satnam’s image and are on the bridge with her now. Perhaps they have called the police? A shocking thought bubbles to the surface. What if she is too late?

The thought stops her in her tracks. Wouldn’t she be able to tell if something terrible had already happened? Wouldn’t there be a sign? They say you can sense the presence of the dead if you put your mind and your body to it. Nevis has experienced this herself: sometimes, in the quiet of the night, she has sensed her birth mother, Zoe, as if she were waving to her from behind a closed door.