John J Malone / Jake & Helene Justus #4 (1941)

Abandoned by his nearest and dearest, John Malone is left to drink in the New Year solo among the crowd at Joe the Angel's bar. Then, in staggers a complete stranger, bellowing Malone's name and surreptitiously passing him a key--nondescript except for the "114" on its handle--before collapsing and dying from the knife wound in his back.

Still hung over more than a day later, thanks to Captain von Flanagan's unconventional style of interrogation, Malone gets a cable from honeymooning Jake, requesting fare home from Bermuda. Worse, there's bride Helene right on Malone's doorstep. The honeymoon is decidedly over. Neither Justus wants anything to do with the other, except to demonstrate an innate superiority by independently solving the perfect-crime puzzle that defeated the entire trio after Mona McClane put it to them as a bet on the day of the wedding (The Wrong Murder, series book #3). But the dead house guest discovered at Mona's house shortly after Malone and Helene arrive for cocktails doesn't fit the terms of Mona's puzzle. Instead, he bears a knife wound that's an exact match for the bar stiff's. And a slip of paper reading only "114."

Happy New Year.