“John Bartholomew!” Polly said, halting. “But he’s already gone back. In October.”

He stopped and faced her. “Who told you that?”

“Eileen. She said he went back immediately after he was injured in the bombing on October tenth.”

“Eileen knew about Bartholomew?” he said, grabbing Polly by the arms. “Why the hell didn’t she say something?”

“She wasn’t there when you and I discussed past historians who’d been here, and I didn’t find out about him till after you’d left for Bletchley Park. And since he was already gone—”

Mike shook his head. “He’s not gone. She got her dates wrong. And he wasn’t injured—another member of the fire watch was, and Bartholomew saved his life. And it didn’t happen in October, it was tonight.” They’d reached the Bayswater Road. “Damn it,” he said, looking up and down the empty street. “What the hell’s happened to all the taxis?”

“It’ll have to be the tube,” Polly said.

They hurried into Notting Hill Gate and down to the Central Line. A train was just pulling in, and the car they got on was, thankfully, empty, so they could talk. “You’re certain Bartholomew was here on the twenty-ninth?” she asked.

“Yeah, I heard him give a lecture on it. He told all about the incendiaries and the tide being out so they didn’t have any water to fight the fires and the Wren churches burning and the fire watch saving St. Paul’s. He was up there on the roofs with them. Damn it. He’s been here this whole time! If I’d only known—” He broke off. “Well, it can’t be helped now. I just hope we can get to him in time—”

“In time? But if you know he’s at St. Paul’s—”

“He’s there tonight, but that’s all. Eileen was right about that part of it. He went back to Oxford immediately after the raid. Which means he leaves tomorrow morning. We’ve only got a few hours. What time do the raids start tonight?”

“6:17, though that doesn’t mean the attack on St. Paul’s began then. It might have been later.”

“When did the sirens go?”

“I don’t know, but all the ones this month have gone at least twenty minutes before the planes arrived.”

“So we’ve got till at least 5:45.” He looked at his watch. “It’s a quarter to two now. That gives us four hours, which should be more than enough to find him.”

The train was pulling in to Holborn. “We change trains here,” she said, and led him quickly to the Northern Line platform, which was crowded with waiting passengers.

She had to wait till they were on the train before she was able to say, “But I don’t understand. If you knew he was here—”

“I didn’t know. He said the night St. Paul’s nearly burned down was the worst night of the Blitz, and you said that was May tenth, and since he’d said in his lecture that his assignment had lasted three months, I didn’t think he’d be here till February.”