Roland holds a hand up as Safa goes to speak. ‘I did not predict your reactions, which was stupid of me, completely stupid. How I did not take into account your backgrounds is beyond stupid, so,’ he says, spreading his shaking hands out, ‘I am sorry . . . and I am also sorry for the . . . the bloody mess that ensued after, but we are rushing and doing things so fast that none of us really has any idea what we are doing.’ He stops, blowing air out from puffed-out cheeks.

‘I don’t know how to explain it so you’ll listen to the end and remain calm . . . truly.’ He looks at them imploringly, his hands trembling as he rests them on the desk. ‘We do not have the capacity to deal with you other than drugging you, and I don’t think we can use that drug again. We have no real medical facilities here or medical professionals and the only way to get treatment is to go back, which really is not an option.’

Ben listens intently, registering the words go back. He looks at Harry then at Safa, his mind processing the time periods they are from, then to the view out the window to the dinosaurs. He touches his nose as though feeling for blood and realises his headache is still there, the dizziness, although lessening, is still there too. ‘Oxygen,’ he mutters, then looks up at Roland. ‘Oxygen toxicity.’

‘Ach,’ Harry says, nodding as he makes the same connection.

‘What is?’ Safa asks.

‘Very good, Mr Ryder,’ Roland says, watching Ben closely. ‘We are in the Cretaceous period. The oxygen levels here are far higher than anything humans are used to.’

‘That can kill us,’ Ben replies quickly.

‘What?’ Safa asks again.

‘Like diving, miss,’ Harry says. ‘Have you heard of the bends?’

‘Oh, right,’ Safa says in alarm.

‘We need to leave here,’ Ben says, rising to his feet. ‘Seriously . . . that level of oxygen will kill in . . .’

‘You have all been medicated to prevent any toxicity,’ Roland says, holding his hands out to offer reassurance. ‘The effects will recede. Indeed, Malcolm, Konrad and I have been here for three weeks and we have no effects now.’

‘Medication?’ Ben asks, still standing. ‘There isn’t any medication for—’

‘There is,’ Roland says, cutting him off. ‘Let me explain. Please, let me explain. Everything will become clear.’

Ben sits down, partly because he knows he needs to listen but mostly because he stood up too fast and his head is swimming again.

‘Malcolm and Konrad are terrified of you,’ Roland continues, unsure of where to start or what to say. ‘It was a stupid, stupid thing to do, bringing people like you back without precautions . . .’

‘People like us?’ Ben asks. ‘A soldier, a police officer and an insurance investigator?’