‘Get out of my way, Tash, please.’ She puts her arms out and gives Tash a hard shove, then finds herself running. A handful of students she does not know are standing waiting for the lift. She runs towards the stairs. On the ground floor she pauses to catch her breath.

There are things she knows, things she has kept from the police, from Honor, from everyone. The conversation that evening when Satnam reached for the TV remote and, switching it to off, said, ‘I’m thinking of leaving Avon.’

‘Why?’ Nevis asked, puzzled. Satnam had never given any hint that this was on her mind.

‘I’ve had enough.’

‘But you’ve been doing brilliantly.’ This was true. Satnam had struggled towards the end of the first year but since the autumn her grade average had shot up.

‘There are things you don’t know about, Nevis. I wish I could tell you, but I can’t.’

A sharp stab of rejection hit Nevis between the eyes. She said, ‘I thought we were best mates.’

Satnam reached out and took her hand. ‘We are, and that’s why I can’t tell you.’

Nevis felt herself pull away. The pain between her eyes reached around her head like a badly fitting hat. Rising from the sofa then, she’d said, ‘I’m going to the library.’

She moved out into the hallway and grabbed her backpack from her room. When she returned, Satnam was standing by the door, her hands pressed together in a pleading gesture. ‘We could leave Avon together, transfer somewhere else.’

But Nevis’s legs were already moving from under her, propelling her away from the source of her anguish. Sweeping past Satnam she swung open the front door and tumbled out of the flat onto the landing. She had already reached the bottom of the stairs and had her hand on the door when she heard Satnam cry out, ‘Nevis, come back, please.’

The phrase haunts her now. The desperation in Satnam’s voice. The cruel way she had ignored it, selfishly caught up in her own muddled feelings of rejection, her fear of having to expose herself. Satnam had been about to confide in her, to share her secret and all she could think about was the secret that she, Nevis, was keeping. If she’d only turned and climbed the stairs, they could have sat back down on the sofa and finished their chips and they could have talked. But there was no way back from her wounded pride. Her stupidity. That pain which clutched her skull. She saw now how much keeping her own secret had twisted her, how it had crept in and poisoned the only real friendship she had ever had. Satnam had offered her a chance to break away from all that but when it came to it, her courage had failed her and she’d abandoned her friend when Satnam had most needed her support.