‘However, in light of the connection with Mr Sleder, I am convinced it is the second option Operation Angel is going for: nuclear explosives. The most effective place to put a nuclear explosive would be actually inside the core itself. Only a very small device indeed need be used to set off a chain reaction that would completely vapourize the core – effectively turn the entire core into a massive atom bomb. The explosion itself would not be particularly large in comparison with other nuclear weapons, but the release of radioactivity would be on an unprecedented scale – many times larger than that any existing nuclear weapon might cause.’

‘How would someone get this nuclear explosive into a core?’ asked Fifeshire.

Quoit smiled. It was the first time I had seen him smile, and it wasn’t a particularly heartening sight. It reminded me of the face of a python I had once watched, just after it had swallowed a rabbit. ‘Disguised as a fuel element,’ he said.

There was a long silence, then Quoit continued.

‘Getting six men to infiltrate a power station might be a problem; but getting in one small fuel element, a few feet long, a few inches in diameter, would be the easiest thing in the world. No one would bat an eyelid. Hundreds arrive every week.’

‘Do all reactors use the same type of fuel?’ asked Fife-shire.

‘No, they don’t, and the elements vary from reactor to reactor; but the manufacturing companies usually make the fuel for a variety of reactors.’

‘And how is it put into the reactor?’

‘Again it varies. On some types – some older reactors, and the pressurized-water reactors – they have to be shut down at intervals – three months, six months, a year, it depends. But on many types, the refuelling is continual, done by a machine. The reactor might have twenty-eight thousand elements in it, which stay in for about a year. About thirty-five a day are taken out and replaced. Just one accomplice in the fuel storage would be all that was needed to slip the sabotaged element in on the right day.’

‘To how many reactors could this theory of yours apply?’