“We need to find the submarine and stop it from sailing,” he said. “But neither Bow Street nor the Admiralty have enough manpower to start searching thousands of warehouses—assuming it’s even being stored here in London.” His hair flopped forward as he raked his hand through it. “Where would you even start?”

The question was rhetorical, but Georgie answered it anyway. “You have to narrow down your search. Have you considered that these plans might provide a way to trace him?”

“How?”

“Well, in the first instance, it’s unlikely the submarine has been moved very far from its original location. Blackwall is a busy place—ships unload at all hours of the day and night. Such an unusual vessel would be extremely conspicuous, which suggests they would have limited the time it was visible to the public. Plus, it has to be built close to the river, because they’ll need to test it, so that narrows your search even further.”

He rested his elbows on the desk, mirroring her position. “All that makes perfect sense, Captain Caversteed”—his lips quirked at the teasing nickname—“but even if it is somewhere near Blackwall, there are still hundreds of wharves and warehouses to look at.”

Georgie pulled the paper toward her and pointed at the craft. “Johnstone cannot be building this alone. Look at how complicated it is. It takes a whole team of men to make something even as simple as a rowboat. You need carpenters and block makers, caulkers to pitch the seams, rope makers, riggers to fit the spars and sails, anchor smiths and blacksmiths to provide the chains and all the brass fittings. That’s before you even get to these more unusual, bespoke parts.” She drew her finger over the section that detailed various complicated-looking portholes, piping, and mechanical instruments. “This requires all sorts of gauges and valves.”

She glanced up, and the blood rushed to her face as she realized Wylde was watching her with an amused, intent expression. It was the same kind of look she imagined visitors to a zoo bestowed on some perplexing new creature they’d never encountered before.

Oh, wonderful. Young ladies were supposed to go into raptures over the latest fashion plates in the Journal de Desmoiselles, not display an unseemly interest in technical drawings.

Well, she wasn’t going to hide her curiosity. Wylde would just have to take her as she was.

She cleared her throat. “I know many of the tradesmen who supply the shipbuilding yards, and I can tell you there are very few with the skills to make such complicated bits of machinery.”

His slow smile made her stomach flutter. “I think you might be onto something, Mrs. Wylde. Go on.”