Third, if this was some fraudulent scheme involving Mallory, nobody the old man knew--least of all the postman who used to deliver mail to that very building--would ever have been allowed to appear on the sucker list. Sam Wilson thought some more. Then he hunted up the nearest pay phone and called Mollie. "Mollie? Sam. Look, I just met an old friend of mine--" he picked a name from a billboard visible from the phone booth--"Bill Seagram, you remember him--oh, sure you do; you've just forgotten. Anyway, he's just here for the day and we're going to have dinner and see a show. Don't wait up for me. I might be pretty late.... No, I'm _not_ phoning from Mulligan's.... Now you know me, Mollie; do I ever drink too much?... Yeah, sure, he ought to've asked you too, but he didn't. O.K., he's impolite. Aw, Mollie, don't be like that--" She hung up on him. Sam Wilson stood concealed in a doorway from which he could see the cramped lobby of the Ochterlonie Building. It was ten minutes before somebody entered it and rang for the elevator. The minute Howie Mallory started up with his passenger, Sam darted into the building and started climbing the stairs. He heard Mallory passing him, going down again, but the elevator wasn't visible from the stairway. On the sixth floor, after a quick survey to see that the hall was clear and the doors closed that he had to pass, he found the iron steps to the trapdoor. The roof was just as empty as the other time he had visited it. No, it wasn't. In a corner by the parapet, weighted with a brick to keep it from blowing away, was a large paper bag. Sam picked up the brick and looked inside. It was stuffed with those blue-printed return envelopes. He looked carefully about him. There were buildings all around, towering over the little old Ochterlonie Building. There were plenty of windows from which a curious eye could discern anything happening on that roof. But at night anybody in those buildings would be either working late or cleaning offices, with no reason whatever to go to a window; and Sam was sure nothing was going to happen till after dark. It was a warm day and he had been carrying his coat. He folded it and put it down near the paper bag and sat on it with his back against the parapet. He cursed himself for not having had more foresight; he should have brought something to eat and something to read. Well, he wasn't going to climb down all those stairs and up again. He lighted his pipe and began waiting. He must have dozed off, for he came to himself with a start and found it was almost dark. The paper bag was still there. It was just as well he had slept; now he'd have no trouble staying awake and watching. He might very well be there all night--in fact, he'd have to be, whether anything happened or not. The front door would be locked by now. Mollie would have a fit, but he had his alibi ready.