Laura and Sam were with Freddie Shields in her consulting room at the mill. After she’d made the introductions, Sam spent a few minutes trying to put the visitor at ease. But Freddie Shields was clearly in a state of extreme agitation, barely taking in Sam’s soothing words. Laura noted that he had ignored her advice to get a taxi and had driven here himself.

‘So, what happened to make you so upset, Mr Shields?’ asked Laura.

‘It was horrible. I went out again last night, Dr Archer. And I almost got arrested.’

‘I see,’ Laura said, her voice even. ‘Well, can you tell us what happened — what time this was, where you went and what you did?’

‘It was after midnight. I don’t know how I got there, but I went back to the filling station where I’d been before. It seems I was acting like a mad person — shouting and hammering on the kiosk window.’ He looked down. ‘I must have scared the wits out of the poor kid who worked there. He dialled 999.’

‘You drove there?’ asked Sam.

‘Yes, but I left the car in a lay-by on the other side of the main road. I must have walked right across the A52, but I don’t remember doing so.’ He looked at them anxiously. ‘I don’t remember anything until the police got hold of me.’

For the first time Laura noticed the dressing on Shields’s arm. ‘You injured yourself?’

‘Somehow, although I didn’t feel it. The police saw I had blood all over my coat and they found the wound on my arm. One of the officers put an emergency dressing on it, then I dressed it properly when I got home.’

‘But you have no idea how you came by the injury?’ asked Sam.

‘None at all, and as I say, it didn’t hurt until much later.’

‘And Julia?’ asked Laura. ‘Is she back with you yet?’

He shook his head. ‘I wouldn’t let her, and now I’m glad that I made her stay away. What on earth is the matter with me?’ He looked from one to the other of them helplessly. ‘What am I capable of?’

Sam answered, ‘I’d say that something buried very deeply inside you is struggling to manifest itself, Mr Shields, something from your past. It comes to the surface when you sleep and your defences are down. It’s a little like a recurring nightmare, but instead of remaining asleep in your bed, a part of your brain — the part that controls movement — is still awake, so you get up. The part that controls cognition is still asleep, so you have no awareness of what you are doing.’ He gave Shields a kindly look. ‘It’s frightening, Mr Shields, but not too uncommon. We need to find out what’s troubling you, and when you confront that, I believe the sleepwalking will stop.’