“I'm very discreet,” said William, putting a finger to his lips. “I really am.”

The tea was now ready, and William poured a cup for Angelica.

“You may recall a recent very unfortunate case of poisoning,” Angelica said, as she took a sip of her tea. “A Russian who had got on the wrong side of somebody powerful found that his drink contained a very nasty slow-acting poison. The poor man died.”

William remembered reading about this in the papers. “There was a row over extradition, wasn't there?”

Angelica nodded. “HMG was livid. And we didn't like it at the office. We don't like these people fighting their wars on British soil.”

“Of course not.”

“Well,” Angelica went on, “although that case got into the papers, there was nothing about another attempted poisoning that took place. One of our people was having dinner with a contact in a restaurant. The waiter brought them their main courses, but he had mixed up who had ordered what. Our man was given the boeuf stroganoff instead of the pan-fried salmon. So he swapped the plates around and his contact - a completely innocent member of a foreign embassy - took a couple of forkfuls of the boeuf stroganoff and became violently ill. It had been intended for our man, of course.”

William grimaced. “Just like the Pope.”

“The Pope?”

“Yes,” said William. “John Paul the First - the one who lasted thirty-three days, or whatever it was. He was entertaining some grandee of an Eastern Rite church - one of their patriarchs, or whatever - and his visitor took one sip of his coffee and keeled over.”

Angelica looked dubious. “In the Vatican?”

“In the Vatican,” said William. “And then, of course, the Pope himself succumbed later on. No autopsy. No normal procedures. Just popped into his red slippers and buried. It was very odd, if you ask me.”