“I hate this,” he said at last, leaning toward her, looking intently into her eyes. “You have to believe me. I hate coming in secret like this. I would rather be open, steer the Autolycus into your harbor and say, Here we are, your friends from Grimsby, come to ask your help.’ If Caul had prospered here, the way I hoped he would, that might have been possible. But as it is, who’d trust us? We’re Lost Boys. Burglars. They’d never believe that all we want from you is one book, one single book from your margravine’s library.”

Remora came back into the cabin and handed Wren a tin mug, full of hot, delicious chocolate. “Thank you,” said Wren, glad of the distraction, because she didn’t want Gargle to see how shocked she was by what he had just said. Miss Freya’s library was one of Wren’s favorite places; a treasure cave filled with thousands and thousands of wonderful old books.

It had been on the upper floors of the Winter Palace once, but nobody lived on those floors now and Miss Freya had said it was a waste heating them just for the books’ sake, so the library had been moved downstairs…

“That’s why you can’t find what you want!” she said suddenly. “The books have all been rearranged since you were last here!”

Gargle nodded, smiling at her admiringly. “Quite right,” he said. “It could take our crab-cams weeks to find the right one, and we don’t have weeks to waste. So I was wondering, Miss Natsworthy, if you’d help us.”

Wren had just taken a slurp of chocolate. Anchorage’s supplies of chocolate had run out years ago, and she had forgotten how good it tasted, but when Gargle asked for her help she almost choked on it. “Me?” she spluttered. “I’m not a burglar…”

“I wouldn’t ask you to become one,” said Gargle. “But your father’s a clever man. Friendly with the margravine, from what I remember. I bet you could find out from him where the book we want might be. Just find it and tell me, and I’ll send Remora in to do the rest. It’s called the Tin Book.”