The match was burning low.

“There’s more,” she said, and shook that flame out too. “I’ll tell you this but once. You can get Silver to read it properly after you’ve set off.” She lit a final match, but only used it to light a cigarette. She said in a low voice, “The last part tells where the German submarines will be tonight.”

I sat agog, my mouth hanging open.

“Just off Bell Rock Light,” she added. “It says. A ‘wolf pack,’ they call it, six of ’em hunting together. Their coordinates look like Jerry military mumbo-jumbo to me, but Bell Rock’s clear enough.”

She laughed at me gaping, and held her cigarette to my lips. I took a long drag, but the faint red glow wasn’t bright enough to light the miraculous sheet of paper lying in my lap.

What had I said to Phyllis, on the morning of 7 November, two weeks ago?

I want to know where their submarines are. Some wee thing. One surprising smack in their faces.

“Buckets of blood, I have to get going,” I said. “Drive.”

I folded the page and tucked it into my thigh pocket, and pelted Ellen with questions as she drove.

“How can we trust the old woman? Maybe she’s just having fun with the girl. And what about her—Louisa—you only met her this week! Isn’t she terribly young? Is this cipher machine real, anyway? Have you seen it yourself?”

“I don’t know. Maybe. Aye, she’s young. And no, I have not. But I can tell you Louisa is as sound as you or me. Braver than me. You should have seen her stand up to that Jerry! I trust her, and she trusts Jane, and—”

“And we’ve nothing to lose.” I couldn’t believe my luck. “You know what? I’d rather go on a wild-goose chase for Nan Campbell’s old auntie than take another blind order from Wing Commander Talbot Cromwell.”

Ellen pulled up by my Blenheim and told me, “Louisa says you were lucky. She only managed to work it out because it was a full transmission. If any bit’s missing, the letters get in a guddle. So tell your sparks to take care what he copies down.”

The plane loomed above us, shadow on shadow; Chip was a stocky, smaller shadow heffalumping about against the sky as he climbed into the rear hatch. We were being sent on patrol again, bombed up this time, to escort navy ships heading into Edinburgh through the Firth of Forth.

Silver yanked open the door of the Tilly.

“Thank goodness you’re here; I was worried I’d have to do the flying myself tonight,” he said. “Then you really would be in trouble.”