‘Among other things,’ said the Doctor. ‘Many other things, actually. Lots of them you’d never even suspect you could become a Doctor of. Like cheese – but only the stinky, blue kind.’

Green made another note.

‘So you’ve not seen the faces, then?’ asked the Doctor. ‘No, of course you haven’t. Limited imagination, no psychic resonance. You two wouldn’t see the faces if they, well … stared you in the face. Listen to me carefully: I have to get back to the hospital.’

‘You going nowhere,’ said Grey. ‘Not while you’re being questioned on suspicion of murder.’

‘I didn’t murder anyone!’ cried the Doctor. ‘It was your officer who severed the link between Ben and the Shroud.’

Green scribbled in his notebook. ‘The Shroud?’

‘The alien!’ said the Doctor. ‘The woman holding Ben’s hand.’

‘We do have two females in custody,’ said Green, flicking back through his notes. ‘A Miss Mae Callon and a Miss Clara Oswald.’ He looked up at the Doctor. ‘Are you saying one of these two women killed Mr Parsons?’

‘No, of course not,’ replied the Doctor. ‘It was the other woman. The one with the dog’s eyes.’

Green checked his paperwork again. ‘The arresting officer said he initially thought there were three women present at the murder scene,’ he said to his colleague, ‘but he later corrected that figure down to two. There is no mention of a woman “with dog’s eyes”.’

The Doctor sighed. ‘That’s because she disappeared as soon as your officer pulled Ben away from her. He was already dead. She couldn’t feed on his grief any longer …’ He gasped, his eyes wide. ‘Of course! Don’t you see? It’s the Kübler-Ross model! She was right!’

Green looked confused. ‘Kübler who?’

‘Elisabeth Kübler-Ross,’ cried the Doctor. ‘She posited there were five stages of grief – denial, anger, bargaining, depression and acceptance. I argued with her at the time, but she was right. It’s all in the book she published in 1969.’

‘1969?’ queried Grey. ‘You do realise this is 1963?’

‘Yes, sorry,’ said the Doctor. ‘It’s in the book she’s going to publish in 1969. It fits perfectly. Ben kept saying it couldn’t be happening. He was in denial. The longer people stay connected to the Shroud, the further they’ll progress – and when they reach acceptance …’ He reached across the table to snatch Green’s notepad and pen, then began to scribble out equations at a furious rate.

Green watched him work for a second, then leaned forward. ‘Sir, please don’t take offence, but have you ever been a resident of an institution of any kind?’

‘For a little while,’ said the Doctor without looking up from his calculations. ‘It was Bedlam.’

‘You mean it was a chaotic place?’ said Green. ‘Badly run? Is that how you managed to escape?’

‘What? No. It was called Bedlam,’ said the Doctor. ‘I spent my gap year there. Nice place once you got used to all the wailing and gnashing of teeth. Good gruel, too, if I recall. Of course, it had gone downhill by the time I went to visit Peter Streete there after he’d gone mad designing the Globe theatre.’ He finished his work and sat back, a look of horror on his face. ‘Eleven hours.’

Grey shared another glance with his colleague. ‘Sir?’

The Doctor jumped to his feet again and began to pace back and forth. ‘The Shroud aren’t just feeding on the grief – they’re cultivating it. Sowing the seeds for their own nourishment. The epicentre is here in Dallas, because of President Kennedy’s assassination – but it will spread to the rest of the planet within eleven hours, and if the human race reaches the acceptance stage before I can find a way to stop the attack, there’ll be no way to reverse it.’

‘This is connected to the death of the President?’ asked Grey.

‘Of course it is!’ cried the Doctor. ‘That’s the event the Shroud were waiting for. Oh, if only Jack was here now. He’d tell you to listen to me.’

‘Are you saying you knew President Kennedy?’

‘Yes, well – no. Sort of. I met him back in the 1950s, just before I accidentally got engaged to Marilyn Monroe at Frank Sinatra’s house.’

Green dropped his notebook onto the table and rubbed his forehead with his hand. ‘I’m getting a headache.’

The Doctor strode over to a mirror filling one entire wall of the interview room and banged on the glass. ‘Hello? I know this is a two-way mirror, and there’s someone on the other side of it. You in there – I have to talk to you.’ There was no response. He sighed. ‘Believe me, we really don’t have the time for this. If you won’t come out, I’ll just have to clear the glass,’ he warned. He reached into his jacket pocket, then sighed again. ‘Did you really have to confiscate my screwdriver?’ he asked, turning to Grey and Green.

‘Screwdriver? What are you talking about?’ demanded Grey.

The Doctor turned back to the mirror. ‘Whoever you are, you’re the one in charge,’ he said. ‘So please get Abbott and Costello out of here and let me speak to someone who hasn’t got the imagination of a piece of toast!’

The door opened and an older man in an ill-fitting chequered suit entered the room. The Doctor looked up at him with a smile. ‘If you lot were doing this properly, he’d be about to tell us that he’s just one day away from retirement, and that he’s getting too old for this poop.’

The new arrival ignored the Doctor’s comment. ‘I’ll take it from here,’ he told the detectives.

‘On whose authority?’ demanded Green.

The man in the bad suit flipped open his wallet to reveal a gold badge inside. ‘FBI,’ he said flatly.

Grumbling, Grey and Green collected up their notes and marched out of the room, slamming the door behind them. The older man took one of the now vacant chairs.

The Doctor smiled. ‘The man behind the mirror, I presume.’

‘My name is Special Agent Warren Skeet,’ said the man, folding his arms. ‘Tell me about the Shroud.’ The Doctor sat forward. ‘You believe me?’

‘I didn’t say that.’

‘You don’t have to,’ said the Doctor. ‘I can tell from the look in your eyes.’ He sat forward. ‘Who did you see?’

‘My partner,’ said Warren. ‘Jock.’

‘But Jock is dead,’ said the Doctor. ‘Am I right?’

Warren remained silent.

‘How did you get away from Jock?’

‘His face was on a window pane,’ said Warren. ‘I smashed it. He said some things …’

‘Then you’re one of the lucky ones,’ said the Doctor.

‘Can you help the people who have seen the faces?’

‘Not from here, I can’t.’

‘Letting you out could cost me my job.’

‘Keeping me here could cost you your planet.’

Warren took a deep breath, then pulled a coin from his pocket. He flipped it. ‘Tails,’ he said. ‘You’re free to go.’ He produced the sonic screwdriver from his pocket and slid it across the table. ‘What do you need from me?’

The Doctor snatched up the sonic, spun it and slipped it inside his jacket. ‘First, you can let my friends out,’ he said. ‘And then I need to get back to the hospital. That’s where the biggest concentration of faces is.’

‘I wasn’t enjoying this career anyway,’ said Warren, pushing his chair back and standing up. ‘Let’s go.’ He pulled open the door, the Doctor at his heels – then they both stopped suddenly.

Green suit was standing right outside the door, holding hands with a woman in a blue veil. He was muttering, just like Ben. ‘This isn’t happening. It can’t be happening.’

‘Don’t touch them!’ said the Doctor, pulling Warren back. ‘Either of them.’ He stepped out into the corridor, pressing his back against the wall to avoid accidentally rubbing against Green.

‘What’s happened to him?’

‘It’s the faces,’ said the Doctor. ‘The Shroud. This is what happens when they finally push through.’

‘Can you help him?’ asked Warren. ‘Get him away from her?’

The Doctor ran his sonic up and down Green’s body, then over the hand through which he was connected to the alien. ‘I’m sorry,’ he said, checking the readings. ‘He’s been in there for several minutes. If I try to break the link, he’ll die just like Ben Parsons did.’