Mildmay apparently told the waiter that he was expecting friends, for the man swiftly laid two extra places, and he had hardly finished when two middle-aged men entered, greeted their friend, and took their seats. Their appearance surprised Falconer, for they were flashily-attired, and evidently not of the same class as himself.
In a few moments all three were bending towards each other. One of the new-comers was apparently relating something in a low, confidential tone, and when he had finished, the trio burst into loud, triumphant laughter. Then it did not take long to realise that they were celebrating some occasion, for champagne was soon upon the table and they commenced an expensive meal.
Time after time Falconer endeavoured to catch some word of the conversation, but failed. Yet, whoever the men were, he felt instinctively that they were West End undesirables. After their dinner, they strolled together into St. James’s Street, where Mildmay parted from them and turned towards Pall Mall, while the pair went on into Piccadilly. After walking some distance they entered a bar in Vine Street; yet Geoffrey dare not go in after them for fear of being recognised. Nevertheless, he had ascertained that Mr. Mildmay kept rather curious company.
A couple of days later Falconer, glancing at the register of messages passing between Paris and London, saw that during the night another message for Mildmay had been received. He referred to the tape record, and found that it was in code, as before, rather longer, that it had been dispatched from Tours, and was signed by the initials “M. C.”
That same evening he called again upon the liftman in Ryder Street, and inquired if the electric motor had been running.
“I haven’t heard it for quite a fortnight now, sir,” replied the man. “Last night Mr. Mildmay had two friends here: one man in grey, and the other in a blue suit. Both were middle-aged.”
Geoffrey at once described the two men who had dined with Mildmay in Jermyn Street.
“Yes. That’s them, sir. Shady customers, I should take ’em to be.”
“Just my own opinion,” declared Falconer. “But I’d dearly love to know why the dining-room is kept locked, and the reason that half-horse power motor is there.”
“So would I, sir,” laughed the man. “But, after all, I expect the explanation would be quite simple. I’ve wondered whether he’s experimenting with something or other. At one place I was at we had the same mysteriously locked room. But it turned out that the tenant was a doctor, and was experimenting with the culture of the bacteria of deadly diseases. And that was why he kept the door locked.”