“Hush, my dear,” he interrupted, holding out his hand.  “Don’t abuse me.  I am not angry with you—­not in the least—­and I am going to prove it.  I shall oppose any search warrant which you might apply for, Mr. Shopland, and I think I can oppose it with success.  But I invite you two, Miss Hyslop and Mr. Ledsam, to my party on Thursday night.  Once under my roof you shall have carte blanche.  You can wander where you please, knock the walls for secret hiding-places, stamp upon the floor for oubliettes.  Upstairs or down, the cellars and the lofts, the grounds and the park, the whole of my domain is for you from midnight on Thursday until four o’clock.  What do you say, Mr. Shopland?  Does my offer satisfy you?”

The detective hesitated.

“I should prefer an invitation for myself,” he declared bluntly.

Sir Timothy shook his head.

“Alas, my dear Mr. Shopland,” he regretted, “that is impossible!  If I had only myself to consider I would not hesitate.  Personally I like you.  You amuse me more than any one I have met for a long time.  But unfortunately I have my guests to consider!  You must be satisfied with Mr. Ledsam’s report.”

Shopland stroked his stubbly moustache.  It was obvious that he was not in the least disconcerted.

“There are three days between now and then,” he reflected.

“During those three days, of course,” Sir Timothy said drily, “I shall do my best to obliterate all traces of my various crimes.  Still, you are a clever detective, and you can give Mr. Ledsam a few hints.  Take my advice.  You won’t get that search warrant, and if you apply for it none of you will be at my party.”

“I accept,” Shopland decided.

Sir Timothy crossed the room, unlocked the drawer of a magnificent writing-table, and from a little packet drew out two cards of invitation.  They were of small size but thick, and the colour was a brilliant scarlet.  On one he wrote the name of Francis, the other he filled in for Miss Hyslop.

“Miss Daisy Hyslop,” he said, “shall we drink a glass of wine together on Thursday evening, and will you decide that although, perhaps, I am not a very satisfactory correspondent, I can at least be an amiable host?”

The girl’s eyes glistened.  She knew very well that the possession of that card meant that for the next few days she would be the envy of every one of her acquaintances.

“Thank you, Sir Timothy,” she replied eagerly.  “You have quite misunderstood me but I should like to come to your party.”

Sir Timothy handed over the cards.  He rang for a servant and bowed the others out.  Francis he detained for a moment.

“Our little duel, my friend, marches,” he said.  “After Thursday night we will speak again of this matter concerning Margaret.  You will know then what you have to face.”

Margaret herself opened the door and looked in.