“You have to hold the mug. My grandmother claims something about the heat in your hands helps with the headache. The person who closed the account wasn’t Mr. Butterfield. You learned that when the real Mr. Butterfield came into the bank today intent on closing the same account.”

“Well…yes.”

“The Butterfield who closed the account seemed elderly,” she went on. “The weather having turned, he arrived swathed in scarves and a hat, wearing a nondescript greatcoat with the collar turned up. If he’s a careful sort of swindler, he wore finger gloves beneath his mittens. He might also be bearded, stooped, and wear tinted spectacles, so your teller can barely describe the man who first came in to close the account.”

She’d even got the tinted spectacles right. “Has the same scheme been attempted at Wentworth and Penrose? Perhaps Mr. Butterfield’s impostor is working a city-wide swindle.” A marginally cheering thought.

“Stealing a wealthy old man’s identity is not complicated when that old man has removed himself from society. His son, secretary, or favorite nephew could pull it off. When the schemer disappears into the night, the old fellow realizes that his funds are at risk. By that time, it’s too late.”

Rex finished the last of his tisane and saluted Mrs. Hatfield with the empty cup. “I am apparently the only bank director in all of London unaware of even the simplest frauds. How in the hell is every teller to know every customer at sight?”

“They can’t,” she said, taking the empty mug from him and setting it on the sideboard. “But there is good news. The bounder who duped you will not run the same rig on you again. He doesn’t dare.”

“He’ll move on to another bank?”

“Very likely to another city, even another country. How much did he get?”

“A couple hundred pounds and half of my self-respect.”

“It could have been thousands, but a smart crook doesn’t want to carry that much ready cash. Because the bank will cover the loss rather than publicize its error, the injured party is the bank, not the old man. Criminals prefer to steal from institutions rather than people, the honorable ones, anyway.”

She knelt to poke up the fire, and the cat leaped down from the reading chair to strop itself against her skirts.

“On that disheartening note,” Rex said, “I should be going. I’m expected at the theater later this evening.” Where the hum of gossip all but obscured the dialogue from the stage half the time—not that Rex was interested in the dialogue. “How does a thief decide which old man to impersonate?”

“Cautiously. Impersonation is a long game, involving employment in the household of the dupe, or a careful observation of him. Will I see you tomorrow?”

“Yes, though I hope you rest from your labors on the Sabbath.”