The Shroud victims began to shuffle away, taking their parasites with them. They re-gathered at the edge of the car park and kept a close eye on the Doctor and his friends.

‘What can we do?’ said Wobblebottom. ‘There are only a hundred of us. We can’t treat a whole world in three hours.

‘I can help you spread your cheer,’ said the Doctor. ‘But first, I have jobs for you all. Clowns – get your costumes and props and prepare to get to work.’ He spun to face Mae and Warren. ‘You two – have you noticed anything odd about the victims of the Shroud?’

‘Other than the fact that they’re all begging us for help, not much,’ said Warren.

‘I have,’ said Mae. ‘They’re all adults. We’ve hardly seen any children.’

‘Precisely!’ beamed the Doctor. ‘Children – mainly – haven’t had to endure the same levels of grief that adults have. They haven’t lost people who are important to them and, if they have, they’ve been protected from the very worst feelings. Sadly, there are exceptions – but we’re going to have to ignore those for the moment.’

‘Why?’ asked Warren. ‘What do you want us to do?’

‘Round up as many children as you can,’ said the Doctor. ‘Sammy – the young boy we left with Edith Thomas on our way to the newspaper office. Peggy in the police station cells. As many young people as you can find. They’ll be scared but, if you can persuade them to join us, they’ll swell our numbers considerably. Take the clown car once the props have been unloaded. Fill it with kids!’

‘What about me?’ asked Clara.

‘You and I are heading back to the TARDIS,’ said the Doctor. ‘But there’s just one little thing I have to do first …’ He bounded up the few remaining steps and into the hospital reception area, Clara at his heels.

‘You again!’ exclaimed the guard he’d been stopped by earlier. ‘No tricks this time.’

‘Wouldn’t dream of it,’ said the Doctor, whipping out his psychic paper. ‘Not when we’ve got permission from President Lyndon Johnson himself to come inside.’

The soldier took the psychic paper and stared at it in disbelief. ‘Access all areas,’ he read aloud.

‘And all equipment,’ said the Doctor, retrieving the paper. ‘Which includes your radio.’ He held out his hand. ‘May I?’

The guard lifted the handset from his radio and passed it to the Doctor, who pressed the talk button and spoke into it. ‘Testing, testing, one, two, three … Captain Keating, are you receiving me, over?’

After a second, Keating’s voice echoed tinnily through the speaker on the front of the box. ‘Doctor? Is that you?’

‘It most certainly is,’ the Doctor replied. ‘How’s the General?’

‘Sleeping like a baby,’ said Captain Keating. ‘Was your trip a success?’

‘Absolutely!’ the Doctor exclaimed. ‘And I think I have a way to make the Shroud release their grip on people, but I’ll need some things from you.’

‘Just name them.’

‘I was hoping you would say that,’ said the Doctor with a wink to Clara. ‘I’ll need all your vehicles – with drivers, a loudspeaker system, and all the pillowcases your men can find.’

There was a brief silence. ‘Whatever you say, Doctor. Anything else?’

‘There is one other thing …’

Clara smiled to the bemused guard on duty as the Doctor turned away and rattled off another request. ‘Don’t worry,’ she said kindly. ‘He has this effect on most people.’

The Doctor spun and tossed the handset back to the guard, then held out his arm for Clara. ‘If you would be so kind, Miss Oswald …’

Clara took the Doctor’s arm. ‘Lead the way!’

Once inside the TARDIS, the Doctor hurried down the steps from the console level and began to root around inside a cupboard. Clara closed the doors and leaned back against them with a sigh.

‘What’s wrong?’ asked the Doctor, not looking up from his search.

‘We can’t do it, can we?’ Clara replied. ‘Wobblebottom’s right. A hundred Clowns and a handful of children against millions of Shroud. We’re vastly outnumbered.’

The Doctor stepped out of the cupboard and faced her. ‘The Shroud focus on negative emotions,’ he said. ‘We have to be different. Right now, we need to have hope.’ He spun back to the cupboard. ‘Besides, I just might be able to give the Clowns an advantage.’

He pulled out a large wooden chest and began to rummage through a pile of electrical equipment inside – old kettles, battered TV sets, computer motherboards and more. Every now and again, he would like the look of a piece and set it aside on the floor before going back for more.

‘Hope it is, then,’ said Clara. ‘What can I do to help?’

‘Wires,’ said the Doctor, pointing to a corridor with a broken desk lamp. ‘Down there, fourth turning on the left, second room on the right – you’ll find a workroom with lots of wiring hanging from hooks on the wall. Bring me the lot.’

Clara hurried away down the corridor. It looked exactly the same as every other corridor she’d explored during her time on board the TARDIS, and she wondered how the Doctor managed to keep track of them all – especially as he occasionally got lost himself. Only last week, he’d promised her a tour of the aquarium, but had been forced to give up on it after opening doors to the kitchen, the library and two separate rooms filled with what appeared to be boxes of multicoloured scarves.

‘Fourth on the left …’ She turned into yet another identical corridor and made for the second door on the right. Swinging it open, she was blasted in the face with a burst of hot steam. She ducked back out into the corridor, allowing the clouds to clear, then peeked back inside. The room was lined with wooden panels, in front of which sat wooden-slatted benches.

‘A sauna,’ she said to herself, making a mental note to return on a quieter day. She closed the door and tried the next room along, just in case. ‘Aha!’

This was the workroom. Tools of all shapes, sizes and materials lay scattered about, or wedged into any number of toolboxes that dotted the floor. There, on the back wall, were coils of wire.

Clara unhooked them, slipping each new coil over her arm to carry it. By the time she was finished, both arms were full and she had several loops of wire draped around her neck. She waddled back to the control room, struggling under the weight.

‘At last!’ cried the Doctor, jumping up.

Clara made to drop the bundles onto the console, but the Doctor raised a hand to stop her.

‘No – don’t move. I can see the one I want …’ He reached for a roll of thin, bronze wire hooked over her right shoulder and snipped off a piece around six inches in length.

‘Perfect!’ said the Doctor. ‘You can take it back now.’

Clara dumped the rest of the wire on the floor. ‘Yeah,’ she said. ‘That’s going to happen.’ She circled the console to examine the gadget the Doctor had built from bits of old electronics. ‘Is that it?’ she asked.

The Doctor slotted the length of wire in place, then held his handiwork up for inspection. It looked like a funnel, with a large opening at one end, and a much narrower hole at the end of a section of pipe at the other. ‘Good, eh?’

‘What does it do?’ Clara asked.

‘Well, it amplifies emotions,’ said the Doctor. ‘Happiness goes in here …’ He gestured to the smaller hole. ‘And comes out here much, much stronger.’

‘The Clowns can use it to treat more people at the same time,’ cried Clara.

‘Exactly,’ said the Doctor. ‘I just need to find a couple of screws to hold this pipe on. Can’t have it falling off.’ He scurried around the central console, examining each piece of equipment. ‘These are the right size,’ he said, pressing his face down beside the keyboard. ‘Could you nip back to the workroom and fetch me a screwdriver?’

Clara folded her arms. ‘A screwdriver? Are you serious?’

‘Yes,’ said the Doctor. ‘I need to take the screws out of here and— Oh!’ Slowly, he reached inside his jacket and pulled out his sonic. ‘Do you know, I don’t think I’ve ever used this for actually removing screws before …’