“Muscle memory,” said Gwen. “Where did you learn to lead so well?”

“All-girls boarding school,” said Iris. “We took turns. They said I was the best boy there. All the girls wanted to dance with me. Let’s try a spin. Excellent! Now, the hallway’s too narrow for a full waltz, but we could do the basics. And one, two, three!”

They whirled down the hallway.

“Frame, darling,” said Iris as they turned back in the other direction.

“Oh, that brings back memories,” said Gwen, throwing her shoulders back. “Sorry, I was adjusting to your height.”

“Think of me as a short Greek man with feelings of inadequacy,” said Iris. “Dare we tango?” She struck a fierce pose, stamping her foot, throwing one arm up with the other bent across her chest. “Zee song eez ‘Jalousie’!” she cried. “We weel forgo zee cadenza. Come, my lady—we dance!”

“Yes, you look exactly like Douglas Fairbanks,” said Gwen.

“It’s been said before,” said Iris, swooping in. “Dahmp, da dahhh, dah dah dada dahmp, da dahhh!”

“Are those the actual words? Oh, hello, Mr. MacPherson!”

Their custodian was standing on the landing, gazing up at them openmouthed.

“Hello, Mr. MacPherson,” echoed Iris, waving. “We’re rehearsing a sketch for a party. What do you think?”

“It doesn’t make any sense to me,” said Mr. MacPherson. “What are the two of you supposed to be doing?”

“It’s the one where the maid teaches her mistress the newest dance styles,” explained Iris. “I saw something like it in a two-reeler and thought it would be fun to do ourselves. I don’t suppose you could sing for us—it’s hard for me to do both.”

“Don’t sing, don’t dance, don’t see the point to any of it,” said Mr. MacPherson. “Don’t you go clogging up my hallways with this nonsense.”

“May we remind you that we are the only tenants on this storey,” said Gwen. “There is nothing about not dancing in our lease.”

“Get on with you,” he said. “I’ll be needing to mop that floor soon.”

“Spoilsport,” muttered Iris as they retreated to the safe confines of The Right Sort.

“Thank you for the refresher,” said Gwen. “That was helpful. Still need to try the rumba and the quickstep, but I think my memory has been sufficiently jogged. Oh, it’s about time for us to depart. Hand me my cape, will you, Millie?”

“Yes, milady,” said Iris. “I should put it on for you, shouldn’t I?” She stood behind Gwen and fastened it around her neck, standing on tiptoe to reach. “Very good, milady,” Iris said. “Your chariot awaits.”

They walked down the steps. Iris held the front door for Gwen.

Captain Timothy Palfrey of the Grenadiers stood in full dress uniform in front of an idling cab. He removed his cap upon seeing Gwen.

“Mrs. Bainbridge, you are a vision,” he said. “This humble soldier is honoured to be your escort tonight.”

“Thank you, Captain,” said Mrs. Bainbridge. “Millie, you may ride in front.”

“Yes, ma’am,” said Sparks, keeping her head down as Palfrey held the door open for her.