She took it calmly enough, but later on, as I was taking an electric flash from the drawer of the hall table and putting it in my overcoat pocket, she came on me, and I thought she looked surprised.

During the afternoon I was beset with doubts and uneasiness.  Suppose she called up my office and found that the client I had named was not in town?  It is undoubtedly true that a tangled web we weave when first we practise to deceive, for on my return to the office I was at once quite certain that Mrs. Johnson would telephone and make the inquiry.

After some debate I called my secretary and told her to say, if such a message came in, that Mr. Forbes was in town and that I had an appointment with him.  As a matter of fact, no such inquiry came in, but as Miss Joyce, my secretary, knew that Mr. Forbes was in Europe, I was conscious for some months afterwards that Miss Joyce’s eyes occasionally rested on me in a speculative and suspicious manner.

Other things also increased my uneasiness as the day wore on.  There was, for instance, the matter of the back door to the Wells house.  Nothing was more unlikely than that the key would still be hanging there.  I must, therefore, get a key.

At three o’clock I sent the office-boy out for a back-door key.  He looked so surprised that I explained that we had lost our key, and that I required an assortment of keys of all sizes.

“What sort of key?” he demanded, eyeing me, with his feet apart.

“Just an ordinary key,” I said.  “Not a Yale key.  Nothing fancy.  Just a plain back-door key.”  At something after four my wife called up, in great excitement.  A boy and a man had been to the house and had fitted an extra key to the back door, which had two excellent ones already.  She was quite hysterical, and had sent for the police, but the officer had arrived after they had gone.

“They are burglars, of course!” she said.  “Burglars often have boys with them, to go through the pantry windows.  I’m so nervous I could scream.”

I tried to tell her that if the door was unlocked there was no need to use the pantry window, but she rang off quickly and, I thought, coldly.  Not, however, before she had said that my plan to spend the evening out was evidently known in the underworld!

By going through my desk I found a number of keys, mostly trunk keys and one the key to a dog-collar.  But late in the afternoon I visited a client of mine who is in the hardware business, and secured quite a selection.  One of them was a skeleton key.  He persisted in regarding the matter as a joke, and poked me between the shoulder-blades as I went out.

“If you’re arrested with all that hardware on you,” he said, “you’ll be held as a first-class burglar.  You are equipped to open anything from a can of tomatoes to the missionary box in church.”

But I felt that already, innocent as I was, I was leaving a trail of suspicion behind me:  Miss Joyce and the office boy, the dealer and my wife.  And I had not started yet.