“The increase in slippage at this point is only two days, which would put me through on the twelfth at the latest, and I will be there less than a day. I’ll be in no danger. Linna, do you have those coordinates?” he called over to her.

“Nearly,” she called back, and Dunworthy took off his watch and began emptying his pockets.

The door to the lab banged open, and Colin came skidding in, waving a handful of papers. “You’re Edward Price,” he said. “You live at eleven Jubilee Place, Chelsea. I brought you two five-pound notes.”

“And I see you’ve changed out of your school blazer into something Wardrobe fondly imagines young boys were wearing during the Blitz,” Dunworthy said.

Colin flushed. “I think I should go with you. With two people looking, we can find Polly twice as fast, and I know where every single bomb fell on the tenth.”

“As do I. Give me my money and identity card.”

“And here’s your ration book,” Colin said, handing them to him. “You might get hungry. I brought you a pocket torch. To help you see where you’re going.”

Dunworthy handed it back. “All that will do is get me arrested by the local ARP warden. Pocket torches weren’t allowed in the blackout.”

“But that’s all the more reason for me to go with you. I can see really well in the dark—”

“You are not going, Colin.”

“But what if you’re hit by a bus? That happened a lot in the blackout. Or get into some other sort of trouble?”

“I will not get into trouble.”

“You did last time,” Colin said, “and I had to rescue you, remember? What if that happens again?”

“It won’t.”

“Mr. Dunworthy?” Linna said from the console. “I have the coordinates if you’re ready.”

“Yes,” he said, and saw Colin dart a calculating glance at the draped folds of the net and the distance between it and where they were standing. “Thank you, Linna, but I need a few more minutes. Colin, on second thought, I believe you’re right about the torch. If I’m to get Polly out quickly, I can’t afford to sprain an ankle falling off a curb.”

“Good,” Colin said, holding the torch out to him.

“No, this one won’t work,” he said. “It’s too modern. And it needs to be fitted with a special blackout hood to eliminate the beam’s being seen from above. Go ask Props if they have one with a hood, and if they haven’t, then paste strips of black paper over the glass. Hurry.”

“Yes, sir,” Colin said, and dashed out.

“You have the coordinates ready?” Dunworthy asked Linna as soon as Colin was gone.

“Yes, sir,” she said. “We can do it as soon as Colin—”

He went over to the door and locked it. “Send me through.”

“But I thought—”

“The last thing I need is a seventeen-year-old tagging along while I’m trying to find a missing historian,” he said, walking over to the net and ducking under its already descending folds. “A seventeen-year-old who, as Badri can attest, has a history of stowing away on journeys to the past.” He centered himself on the grid. “Ready,” he said to her.