There Was an Old Woman by Ellery Queen

aboveboard!’” And the Sergeant shook his head and stamped back to the mansion.
    â€œThe big point is, Thurlow’s already checked back on his ammunition supply,” murmured Ellery. “Then he doesn’t know about the blanks, does he, Dad?”
    â€œNot yet.”
    â€œWorried. All legal and aboveboard, but—worrisome, too, Dad. I think you’d better locate Mr. Thurlow’s armory and appropriate it with dispatch. The stuff’s a menace.”
    â€œIt’s a cinch he’s cached it somewhere cute, like the squirrel he is,” growled the Inspector, “and nobody but he knows where. The boys are keeping an eye on Mr. Thurlow, so it’ll hold for a few minutes. What about this opportunity business, Ellery? Let’s go over the ground to make sure. Just what did you do last night after you left Headquarters with the Colt and S. & W.?”
    â€œI returned to the house here immediately, slipped back into Thurlow’s bedroom, replaced the blank-loaded Colt automatic on the highboy exactly where I’d found it earlier in the evening, then I went to the twins’ room and gave Bob Potts the blank-loaded Smith & Wesson.”
    â€œAnybody spot you entering or leaving Thurlow’s room?”
    â€œI can’t swear, but I’m convinced no one did.”
    â€œThe twins knew about it, though, didn’t they?”
    â€œNaturally.”
    â€œWho else?”
    â€œCharley Paxton and Sheila Potts. All the others had left by the time we discussed the plan to substitute blanks for the live cartridges in the two guns.”
    â€œAll right,” grunted his father, “you left the Colt right where you found it, in Thurlow’s bedroom, you gave Robert his doctored revolver, and then what?”
    â€œI left the twins in their room and went downstairs to the library. Charley and Sheila still had Thurlow cornered down there, as I had instructed. Thurlow was in a gay mood—Sheila’d fed him some drinks in an effort to restore his sanity. He insisted on our all going out on a tear, which we did, just as we were—the four of us. We left the house in a group, from the library, cabbed downtown, and spent the entire night at Club Bongo, on East 55th Street. We didn’t get back to the Palace—”
    â€œThe what?”
    â€œForgive me. I’m only using the family’s own terminology. We got back here about a quarter of six this morning.”
    â€œWas Thurlow, Paxton, or Sheila in a position to get to that Colt automatic in Thurlow’s room at any time during the night, after you left it there?”
    â€œThat’s what makes this part of it so beautiful,” declared Ellery. “No, those three were with me, within sight and touch, from the moment I stepped into the library until we got out of the cab at dawn this morning.”
    â€œHow about when you got back? What happened?”
    â€œI left Thurlow, Charley, and Sheila on the lawn, right over there, as you saw. Thurlow’d sent me into the house to fetch his gun. I went up and—” He stopped.
    â€œWhat’s the matter?” asked his father quickly.
    â€œI just remembered,” muttered Ellery. “It seemed to me as I went up that spiral staircase to the landing that I … not exactly heard, but felt someone or something moving in the hall outside the bedrooms.”
    â€œYes?” said the Inspector sharply. “What? Who?”
    â€œI don’t know. I even had the feeling it came from around the area of Thurlow’s door. But that may have been an excited imagination. I was thinking of Thurlow’s apartment.”
    â€œWell, was it or wasn’t it, son? For the love of Peter’s pants! Did somebody come out of Thurlow’s rooms around six A.M .?”
    â€œI can’t say yes, and I can’t say no.”
    â€œVery helpful,” groaned the Inspector. “You got the gun and came right back down