She pulled herself together as she reached the outskirts of Newcastle-under-Lyme and had managed to stem the tears by time she parked the Golf on campus.

She went in the lobby of the Endeavour Building, which stood at the heart of Keele Science Park. The smoked glass and brushed black steel structure was eight storeys high. The security measures were far stricter than anything she’d seen in the lab where she’d first met Dr Abiola. Harri introduced herself to the receptionist, and the bored man handed her a visitor’s pass. She followed his instruction to wait in a seating area opposite the reception desk, where she took the opportunity to wipe her reddened eyes. She checked her make-up on her phone’s selfie camera. She looked puffy and miserable, but there was nothing she could fix in the few minutes she had available. Dr Abiola would have to take what she got: a broken, humiliated failure.

‘Ms Kealty?’

Harri looked up to see a movie star in a black suit. Well, he wasn’t a movie star anyone would recognize, but he had the good looks of an idol.

Harri cleared her throat and straightened her top as she stood. ‘Yes.’

‘Thank you for coming. I’m Nick Sullivan. I run security for the science park. Dr Abiola is waiting for us.’ He smiled to reveal rows of gleaming pearls. ‘If you’ll follow me.’

Harri nodded and followed him silently through the building, passing through long anonymous corridors. They reached a security door near the heart of the ground floor, and Nick tapped a code into a keypad to open it.

When they stepped into the small windowless antechamber on the other side, Harri saw Dr Abiola standing next to a security guard who was posted at a desk by a steel door that looked as though it belonged in a bank vault.

‘Thank you for coming, Ms Kealty,’ Dr Abiola said. ‘I was bothered by an issue you raised when we last met. Nick, if you wouldn’t mind?’

Nick pressed his palm against a scanner beside the steel door.

‘I was suspicious of who you might be working for. I thought you were trying to gather evidence against the university to suggest we might have been negligent in exposing one of our employees to a toxin,’ Dr Abiola said.

Behind her, the steel door slid back an inch from the frame, revealing a pressure seal which deflated.

‘Once I’d had a chance to reflect on our conversation and look further into your background, I took a different view,’ Dr Abiola added.

‘My background?’ Harri asked, suddenly ashamed. Would she ever escape her past?

‘I told you the first time we met that I didn’t believe the allegations surrounding your dismissal . . .’

Harri couldn’t bear to hear it. ‘My dismissal was not a reflection of guilt.’

The heavy door had completed its slow slide. Nick stood beside the open doorway, studying his shoes intently, pretending not to listen, and Harri shrank inside.