“Lenny Smile never existed, Tim!” I explained. “He was a fantasy. I should have known when I saw the details on the gravestone. It said that he was born on April 31, 1955. But that was the first lie. There are only thirty days in April. April 31 doesn’t exist!”

“It was a mistake . . .” Fiona muttered.

“Maybe. But then there was that photograph Carter showed us of ‘Lenny’ standing outside the Café Debussy. You told us that he was allergic to a lot of things, and one of those things was animals. But in the photograph there’s a cat sitting between his feet—and he doesn’t seem to care. The allergy business was a lie. But it was a clever one. It meant that he had a reason not to be seen. He had to stay indoors because he was ill . . .”

Inch by inch, the big wheel carried us farther away from the ground. The rain was hammering against the glass. Looking out, I could barely see the buildings on the north bank of the river. There was Big Ben, but then the rain swept across it, turning it into a series of brown and white streaks.

Tim gaped. “So there was no Lenny Smile!” he exclaimed.

“That’s right. Except when Hoover pretended to be Lenny Smile. Don’t you see? He rented the apartment even though he never actually lived there. Occasionally he went in and out to make it look as if there was someone there. And of course it was Hoover who wrote that letter to Mrs. Lovely.”

“How do you know?”

“Because it was written in green ink. The message we saw in the card on Lenny’s grave was also written in green ink—and it was the same handwriting. I should have seen from the start. It was Hoover we saw at the circus. And he was also there at Brompton Cemetery the day we visited the grave. I should have known it was him as soon as we met him at the Dream Time office.”

“Why?” Tim asked.

“Because Hoover had never met us—but somehow he knew we’d been to Brompton Cemetery. Don’t you remember what he said to us? ‘You know very well that he’s lying there in Brompton Cemetery.’ Those were his exact words. But he only knew we knew because he knew who we were, and he knew who we were because he’d seen us!”

Tim scratched his head. “Could you say that last bit again?”

Fiona looked at me scornfully. “You’re talking nonsense!” she said. “Why would Rodney and I want to invent a man called Lenny Smile?” she continued.