We revived, as best we could, the back-room boffin of a hero with the contents of Hugo Rune’s hip flask.

The back-room boffin came to and coughed somewhat and spluttered.

‘Alan,’ said Hugo Rune. ‘Are you feeling yourself now?’

‘I was searching in my pocket for my keys,’ said the other. ‘I’ll thank you to keep a civil tongue.’

And sadly I shook my head and hoped against hope that I was not about to find myself on the receiving end of a load of ghastly double entendres and cheap knob gags. This, I knew, was not what Alan Turing was all about. Although it would be right up Frankie Howerd’s back alley. So to speak. I helped the hero into a chair and dusted down his tweeds. He certainly had a noble look to him. A noble look and a famous one too. He had one of those big square heads that film stars and politicians seem always to have. They look so big and square when you actually see them in the flesh that it is as if you are seeing one of Gerry Anderson’s puppets brought to life. And it was indeed the case here that Alan Turing bore an uncanny resemblance to Brains out of Thunderbirds. I was very taken with his suit, though. Boleskine tweed, like my own, but in the blue. The man had class.

He had extremely twinkly brown eyes and these now stared at Hugo Rune.

‘Hugo,’ said Alan Turing. ‘What are you doing here?’

‘The matter of the murder,’ the mage replied. ‘McMurdo from the Ministry called me in, as it were.’

‘You should go,’ cried Alan Turing. ‘Go at once!’ And he stared now at me. ‘And take your catamite with you.’

‘Now steady on,’ I said. ‘I am an acolyte, me.’

‘It’s out of control,’ Alan now cried. ‘I fear it will kill us all. In fact I am certain that it will. Go now. Run while you still can.’

‘Where is the rest of your team?’ asked Mr Rune, downing the last of his hip flask’s contents. ‘Not all dead, as that fellow there?’ And he gestured to the ashes on the floor.

‘Outside, in the Anderson shelter.’

I wondered whether Gerry Anderson had invented this.

‘They are all safe,’ Alan continued, ‘as long as they do not come back in here.’

‘So why are you here, my friend?’ Mr Rune asked.

‘I must pull the plug. It is my folly that has brought this upon us. I must, if needs be, pay the price.’

‘I think,’ said Hugo Rune, ‘indeed I know, that you must now tell me all that you know regarding this matter.’

‘I must destroy it. You must leave.’ Alan Turing fluttered his hands about in a futile fashion, imploring that Hugo Rune and I depart.

‘I must know all that you know,’ said Hugo Rune. And with that said, he now hoiked Alan Turing to his feet and dragged him from the room and from the hall and from the building.

And then sat him down upon the gravel drive.

‘Tell me all,’ said Hugo Rune. ‘Tell me all, and now.’

Alan Turing huffed and puffed, but then he told it all.

‘It is this way,’ he said, his big face lit by the moonlight. ‘As you must know, this unit has been assembled to crack German codes. Each member of the team is a genius in their own field. Each was required to pass a test, solve the Daily Telegraph crossword in less than twelve minutes-’

‘I can do that in eight,’ said Hugo Rune. ‘Whilst holding my breath.’

‘I have not the slightest doubt that you can,’ said Alan. ‘But we are not as you. But we are gathered here to beat the Germans in our way. And I did what I did in good faith and through the honest wish to aid my country. You must understand that.’

‘I will understand it better when you explain it to me,’ said Hugo Rune. ‘Although a light is slowly beginning to appear at the end of a long, dark tunnel. Would I be right in believing that you are referring to Colossus?’

‘The computer built by Tommy Flowers,’ I said, ‘at the Post Office Research Station at Dollis Hill.’

‘The same,’ said Alan Turing. ‘Are you with MI6?’

I shook my head. And shrugged my shoulders. And then I scratched at my nose and twiddled my chin.

‘I see,’ said Alan Turing. ‘A Freemason, I understand.’

I looked at Hugo Rune. Who rolled his eyes.

‘Colossus,’ said Alan Turing. ‘A work of genius if ever there was one. You see, Hugo, there are certain things that cannot be improved upon. Certain mathematical theorems. Certain works of engineering. The Merlin engine for the Spitfire. The Tesla coil. These things have been designed and built to the best standard humanly possible and they simply cannot be improved upon. Such was Colossus. But I improved upon it. I added extra components. I upgraded its memory banks. I improved upon perfection. And that a man must never do.’

‘That, by definition, a man can never do,’ said Hugo Rune. ‘So what did you do, Alan?’

Alan Turing gave a great sigh. ‘I gave it life,’ he said.

And I gave a gasp as big as his sigh. ‘You gave it what?’ said I.

‘Life,’ said Alan Turing. ‘Colossus lives. It is a thinking machine. It now thinks independently of those who programme it. It has its own-’

‘Artificial Intelligence,’ I said.

‘Yes,’ said Alan Turing. ‘I couldn’t have put it better myself. That is what it has. Artificial Intelligence. It learns, it thinks. It makes its own decisions.’

‘The flags on the great wall map?’ said Hugo Rune. ‘The strategies, as in a great game of chess?’

‘The work of Colossus.’

‘A work of unworldly genius,’ said the Magus.

‘Indeed, indeed.’ And Alan Turing nodded his big square head. ‘It thinks for itself and it is now in command of the Allied offensive against Germany. It is, in effect, running the war from this side of the English Channel.’

‘And Churchill?’ asked Hugo Rune.

‘He loves every minute of it. Because when we win the war he will take all the credit. No one is ever going to believe that a machine constructed from wires and valves did all the thinking and planned all the military campaigns, are they?’

‘It is not in any history book I have ever read,’ I said.

‘What?’ asked Mr Turing.

‘And how long has this been going on for?’ asked Hugo Rune.

‘About six months.’

‘And would you say that we are winning the war?’

‘Undoubtedly so.’

‘And so where, exactly, is the problem?’

‘The problem,’ cried Alan Turing, his voice rising to an alarming pitch, ‘is that it has started killing my staff. It is eliminating those it considers to be slackers, or not contributing sufficient new ideas regarding the winning of the war. It thrives upon ideas. Ideas are its brain food, as it were.’

‘How many dead?’ asked Hugo Rune.

‘Four,’ said Alan Turing. ‘Mavis the tea lady. She was the first to go. Colossus said that she made the tea too weak. That the operatives needed the noblesse of strong tea-’

‘Have to stop you there,’ said Hugo Rune. ‘Colossus said this? Colossus speaks? And noblesse?’

‘I installed a frequency modulator linked to a vibrating diaphragm. The resultant oscillations mimic speech of a rudimentary nature. It uses words such as noblesse and chivalry. It thinks it is King Arthur.’

I said, ‘What?’

Mr Rune said, ‘What?’

And again we said, ‘What?’ together.