Hoffmann suddenly felt too tired to carry on. He closed his eyes again and leaned his head back against the sofa, then remembered his wound. ‘Sorry. I’m ruining your furniture.’

‘To hell with the furniture.’

He stared at her. She looked older without her make-up, more fragile and – an expression he had never seen before – scared. It pierced him. He managed to smile at her. At first she shook her head, but then – briefly, reluctantly – she smiled back, and just for a moment he dared to hope the whole thing wasn’t that serious: that it would turn out to be some old tramp who had found the entry codes on a scrap of waste paper in the street, and that one day they would laugh about it – his knock on the head (a fire extinguisher!), his mock heroics, her anxiety.

Leclerc came back into the drawing room carrying a couple of clear plastic evidence bags.

‘We found these in the kitchen,’ he said, resuming his seat with a sigh. He held them up. One contained a pair of handcuffs, the other what looked to be a black leather collar with a black golf ball attached to it.

‘What’s that?’ asked Gabrielle.

‘A gag,’ replied Leclerc. ‘It’s new. He probably bought it in a sex shop. They’re very popular with the S and M crowd. With luck we may be able to trace it.’

‘Oh my God!’ She looked in horror at Hoffmann. ‘What was he going to do to us?’

Hoffmann felt faint again, his mouth dry. ‘I don’t know. Kidnap us?’

‘That’s certainly a possibility,’ agreed Leclerc, glancing around the room. ‘You’re a rich man, that’s obvious enough. But I must say that kidnapping is unheard of in Geneva. This is a law-abiding city.’ He took out his pen again. ‘May I ask your occupation?’

‘I’m a physicist.’

‘A physicist.’ Leclerc made a note. He nodded to himself, and raised an eyebrow. ‘That I did not expect. English?’