Dr Ellison dodged around Clara and tossed the sheet over the pool of blood. The head beneath it began to sink back into the ground.

‘Andrew!’ Dr Ellison called, holding out a hand. ‘Come away from the window. It’s gone now.’

‘I … I dropped a blood bag,’ said Andrew, blinking away his tears. ‘It burst open and covered the floor – and there was a face. Sophie’s face!’

‘It’s OK,’ Dr Ellison soothed.

‘No, it is not OK!’ spat a voice. The three of them turned back to look at the sheet on the floor – the blood was starting to soak into it. The face was reforming. ‘If you hadn’t forced me into sneaking around like a guilty schoolgirl, I’d still be alive!’

‘No!’ pleaded Andrew, turning to look at the ground, several stories below. ‘It’s not true!’

Dr Ellison stepped forward, her own eyes growing wet. ‘Andrew,’ she said. ‘Whatever you think is happening, it’s not real. Take my hand and we can talk.’

Andrew Ross raised his eyes once more, gazing into those of his mentor. ‘I’m sorry,’ he said quietly. ‘I have to be with her.’ Then he tumbled backwards out into the air.

The Doctor cradled the new-born baby in his arms and grinned. ‘And after all that, it’s a girl!’

Mae fussed around Ruby, mopping her brow and straightening the bed sheets. ‘What are you going to name her?’ she asked. ‘Have you thought of anything yet?’

Ruby shrugged. ‘I always figured it was going to be a boy, named after his daddy.’

‘What?’ said the Doctor. ‘Scary-flowery-nightdress-head? I think the other children might tease her at school.’

The baby gave a gurgle.

‘Oh, all right,’ said the Doctor. ‘There’s no need to use language like that.’ He handed the baby over to her mother. ‘She says her name is Kill-a-Tron 3000, but I think a more suitable day-to-day version would be Betty.’ He offered Mae a wink, then noticed the nurse at the end of the bed was beginning to come round.

‘Oh, now you decide to wake up!’ he cried. He helped the nurse into a chair. ‘You’ll be just fine in twenty minutes,’ he said kindly. Then he noticed Clara standing in the doorway.

‘Hello!’ he beamed, standing up. ‘We’ve had a great time here. How about you?’

Clara shook her head.

‘Ah. Dr Ellison?’

‘She’s … She’s gone to be with someone. A friend. A … A late friend.’

As Clara spoke, more screams and cries for help began to ring out.

‘We have to find out what’s going on here and put a stop to it,’ said the Doctor. ‘Why this hospital? Why now?’

‘It’s not just the hospital,’ said Mae. ‘Remember my Grandma Betty? That’s how I got this burn in the first place, and it didn’t happen here.’

The Doctor grabbed his jacket. ‘Show me!’

There were more screams and bulging faces as they ran back along the hospital corridors towards the TARDIS. A child’s head stretched out from the lumps in a bowl of oatmeal; the face of an elderly man twisted as it rose from a trolley of soiled sheets; and the sullen woman Clara had seen earlier knelt, sobbing, beside the head of a young soldier as it rose from her scattered bouquet of flowers.

The Doctor tried to help them all as he ran, letting off blast after blast from his sonic at each and every face – but there were just too many of them. He had to find the source of the problem and stop it there.

The trio turned the corner to reach the TARDIS and froze. There, pushing its way out from the pattern of mud spattered on the doors, was another human head. The Doctor grabbed Mae and Clara and dragged them back out of view. ‘Oh, brilliant,’ he hissed. ‘Just what we need.’

Clara nodded, her eyes closed and the back of her neck pressed against the cold stone of the wall. ‘Uncle Reuben.’

The Doctor turned to her. ‘Uncle who?’

‘Uncle Reuben,’ said Clara. ‘Not a real uncle – a friend of the family kind of uncle. I really loved him, though.’

‘No, no, that’s not right,’ said the Doctor. ‘That wasn’t your Uncle Reuben. That was Astrid.’

‘You said that name before. Who’s Astrid?’

The Doctor sighed. ‘Astrid Peth. A waitress who pushed a megalomaniac into a warp engine with a forklift truck so I could stop the Titanic from crashing into Buckingham Palace on Christmas Day.’ He looked away from Clara’s stunned expression. ‘Actually, saying it in one breath like that makes it almost sound unlikely.’

‘Yeah,’ said Clara, raising an eyebrow. ‘Almost.’

‘You’re both wrong,’ Mae insisted. ‘It was Grandma Betty again.’

The Doctor’s eyes lit up. ‘Now that is fascinating!’ he said. ‘We each saw someone different in the mud on the doors.’ He turned to Clara again. ‘Which, by the way, is typical of you. An entire planet filled with bubble bath, and you still manage to get the TARDIS dirty!’

‘Stop fussing!’ Clara cried. ‘Once we’re done here, we’ll fly it to the Planet of the Car Washes, or something.’

‘Fly it?’ said Mae, rubbing her forehead. ‘Planets filled with bubble bath and car washes? What are you two talking about? Is it some kind of secret code?’

‘I’ll explain when we’re not surrounded by hideous heads,’ promised Clara. ‘In the meantime, what are we going to do about the face on the TARDIS door?’

The Doctor grinned. ‘We look again – just for a second!’

So Clara, Mae and the Doctor popped their heads back around the corner – one above the other – to get another look at the muddy face. Then they disappeared again.

‘OK,’ said the Doctor. ‘Who did you see?’

‘Grandma Betty,’ said Mae.

‘Uncle Reuben,’ said Clara. ‘You?’

‘Astrid Peth,’ said the Doctor.

‘But how?’ asked Clara. ‘How are we all seeing different people?’

‘The Shroud must be using psychic connections,’ said the Doctor. ‘Stretching out with mental tentacles – ooh, that is good! Mental tentacles! Remind me to say that again. Stretching out until they touch upon another mind, then they use that person’s memories to form a familiar face. My guess is each Shroud starts out as a random face within a pattern, but they’re constantly reaching out and probing until they find a victim. Then once a connection is made, they scour your mind for someone that you know – someone that you miss – and use your memories of that person to ensnare you.’

‘That’s horrible!’ exclaimed Clara.

The Doctor nodded his agreement. ‘It’s similar to how my psychic paper works, only in a nasty, fishing-for-unhappy-memories way.’

‘So one of those things grabbed me with its tentacle things?’ asked Mae. ‘That’s why I saw my grandma?’

‘Yes, but you fought it,’ said the Doctor. ‘And you’re still fighting it.’

‘But what are these Shroud things?’

‘They’re aliens,’ said the Doctor matter-of-factly.

Mae slumped back against the wall. ‘Now I know I’ve gone mad,’ she said. ‘I could just about cope with my dead grandmother bursting out of my arm – but now you’re talking about little green men from Mars?’

‘I’m pretty sure they’re not from Mars,’ said the Doctor. ‘And they’re not green, as far as I can tell. Although, the aliens that are from Mars are actually green, which is interesting. But they’re not little. And they hisssssss a lot when they speak.’

Clara spotted Mae’s expression of bemusement and stepped in. ‘I know it’s hard to believe,’ she said, ‘but aliens are real. I’ve met a few now and, by and large, they’re very nice people.’

The Doctor adjusted his bow tie with a smirk.

‘You must have heard of the story – back in the 1940s,’ Clara continued. ‘The crashed spaceship in Roswell. Area 51, I think they call it.’

‘Roswell, New Mexico?’ scoffed Mae. ‘But that was just a hoax.’

The Doctor snorted back a laugh. ‘It most definitely was not a hoax. I told them they needed better shields protecting their thermo couplings, but did they believe me? No! And look where it got them.’

‘You have to trust the Doctor on this one,’ Clara said kindly. ‘He’s right.’