The third thing was that Director Tie had picked a name for our operation. ‘They have called this code RECOVERY, and so our operation to crack it is code-named PRIMUS. If you don’t want to head the team, that’s fine: I’ll do it myself and you can be the deputy head. That’s the only concession I’m prepared to make. If you complain any more or try to resign again, I really am going to get cross!’

It was an ultimatum.

I had no choice, but I still had no idea where I should even begin. Thank God for Bureau Chief Liu, who was not only a graduate of the Department of Mathematics at Qinghua University, but had also been involved in cryptography programmes for a very long time. He quickly came up with a suggestion for me. This was a man called Hu Haibo, who had studied in America and been winkled out a few years back by Naval Intelligence to crack ciphers for them. His achievements were amazing; in that short time he had decrypted quite a few high-level foreign ciphers, making himself famous in the field.

Bureau Chief Liu said, ‘He would definitely be our first choice, but I think it’s going to be very difficult to get Naval Intelligence to let him go unless Director Tie makes the request personally.’

After I reported this to Director Tie, he didn’t hesitate for a moment. He went straight to his opposite number in the Navy and asked for a meeting to be set up. Since everyone else concerned was already in Beijing, we just had to wait for Mr Hu to get there the following day. He turned out to be somewhat past forty, dressed in a blue naval uniform, with the pips of a captain. He wore glasses and his hair was crew-cut, and when he spoke he weighed up his words carefully. He seemed to me both highly cultivated and extremely intelligent. When I arrived Director Tie and Bureau Chief Liu had already been talking to him for a while, and whatever they had offered him, Captain Hu had refused. Director Tie introduced us, and then with the air of someone who can’t stand beating about the bush, he said frankly, ‘Well, how about we don’t apply for a formal transfer in the first instance, given that this is likely to be extremely difficult even if you want to go forward with it. Let’s compromise by just borrowing you for a few months. I’ll talk to your boss – is that OK with you?’