Derrick smiled under his heavy moustache, and took a long look at Mr. Tracey. The American was fair and handsome, active in his movements and compact in his frame. He wore fashionable evening-dress, and looked a shrewd, pleasant man of the world, who had travelled much and had his wits about him. The mention he made of arrest showed Derrick that the man was innocent. Not even a Yankee's passion for advertising his goods would hurry a man into the grip of the law if he were in any way guilty. The inspector, however, did not think it wise to lose sight of Tracey, and being diplomatic he behaved towards him in quite an affable way. "You might come with me and see into this matter," he said, moving on. "Rather," rejoined Tracey with alacrity. "I'm dead gone on adventures, and this is a ripper. Wonder if I can get an advertisement out of it? What do you think, sir?" "Well, if your car is missing------" "'Course. The man's raced off with it." "No," denied Mulligan again; "he was with me at the time your car was lost." "Do you think the man you talked to, killed this woman?" asked the inspector, turning sharply on Mulligan. "I do and I don't, sir." "What do you mean by that?" Mulligan scratched his head. "He had the key, and he came out of the house sure enough. But she was singing when he talked to me at the gate. She wasn't dead then." "Then he must be innocent," said Derrick sharply. "Do you know to whom the villa belongs?" "No, sir. Here it is, and you can see that the light's still burning as I left it. I haven't touched the body, sir." "You did right," approved Derrick, swinging open the gate. "Wait, we must look at the name. Your lantern, Mulligan." The light illuminated the black letters on the gate, but before the inspector could pronounce the name, Tracey did it for him. "Ajax Villa--Ajax Villa," said he, stopping; "sakes, it's Fane's house. Don't tell me it's Mrs. Fane--such a fine woman. But it can't be." "Why not?" said Derrick, looking at him suspiciously. "Because the whole family are at the seaside--all except Miss Mason." "Where is she, and who is she?" "Miss Mason is the sister of Mrs. Fane, and she's stopping with the friends I was seeing when my car was stolen." This was a strange discovery, and Derrick looked puzzled. Tracey spoke in all good faith, and seemed quite willing to enter the house. All the same it was queer he should know so much about the matter. As the constable opened the door Derrick asked a question. "You heard Mulligan describe the man who came out of this house," he said; "can you tell me who he is?" "No," confessed Tracey. "I know very little of Mr. Fane and his family. I've never been in this house. But Miss Mason is the bosom friend of the girl I'm going to engineer into the position of Mrs. Tracey. She's Gerty Baldwin at present, and lives at No. 20 Meadow Lane along with her mother and the kids. Now, is there anything else you want, to know, Mr. Inspector?"