“I was gobsmacked,” said Mrs. Bainbridge.

“But then something peculiar happened,” said Sparks. “That same night, we were picked up by British Intelligence and questioned about the late Mr. Magoulias, the still living Mr. X, and the letters. This wouldn’t have happened unless my friend the forger had called them up the moment we left to let them know that we did have the letters, despite the failure at the rendezvous.”

“And the conclusion you drew from that?” prompted Mrs. Bainbridge.

“That we had brought the letters to be verified by the very man who had created them,” said Sparks. She turned to look at the Brigadier, who stood impassively in his mask. “And that he was doing it on behalf of British Intelligence,” she concluded.

“Why would British Intelligence go to all this trouble, Sparks?” the Brigadier asked.

“Why does British Intelligence do anything nowadays?” she asked. “To winnow out the spies in our midst. Which brings us back to the most important question: who killed Magoulias?”

“And the question you should be asking us first is, how did our friend get to the rendezvous point ahead of us?” asked Mrs. Bainbridge. “For that, we must call him as our next witness. Sally?”

The silent manifestation of Sally’s massive physique out of the dark caused a stir in the room.

“Theatre in the round,” he muttered to Mrs. Bainbridge. “I love it!”

He stepped between the fires and held out his arms, embracing the invisible audience.

“O for a Muse of fire, that would ascend the brightest heaven of invention!” he declaimed.

“Sally?” interrupted Mrs. Bainbridge.

“A kingdom for a stage—”

“Sally,” said Sparks.

“Princes to act and monarchs to behold the swelling scene!”

“Sally!” cried the two women together.

“Sorry,” said Sally. “I couldn’t resist. That’s from Henry the Fifth, Act One—”

“We know the bloody play,” called one of the spivs. “Get on with the important bits. You can do the Saint Crispin’s Day speech later.”

“Yeah, after we’re gone,” added another.

“Critics everywhere,” Sally sighed. “Call me Sally. I am a friend and odd-job boy to these two. On Saturday afternoon, at the request of Miss Sparks, I embarked on one of the odder jobs I’ve ever been given. I stood under the window of The Right Sort. A note came fluttering down, giving me the time and place of a rendezvous, though, alas, not one of a romantic nature. We had allowed for a number of contingencies. This one required escape by water. I jumped on a motorcycle, roared through the streets to where I had a boat stashed, and putt-putted my way to a location by Poplar Dock, where I maintained vigil with a pair of opera glasses.

“Shortly after my arrival, I observed a man emerge from the warehouse, toss something into the Thames, then limp off. Minutes later, Miss Sparks and Mrs. Bainbridge came through that same door, and I transported them away.”

“As I stated, we have Mr. X,” said Sparks. “Bring him forwards, lads.”