“Well, it goes like this,” Della said. “Because you’ve come in the room, you must have been the person going out of the room. Therefore, having gone out of the room while you were coming into the room, someone who saw you in the corridor coming into the room, would have known you were going out of the room, and—”
“Oh, I see,” Drake said, “like a puppy chasing his tail, huh?”
“Exactly,” Della agreed, “only the puppy catches his tail. Then, having swallowed himself, he becomes, so to speak, completely self-contained.”
Mason chuckled and said, “Don’t mind her, Paul. She’s filled with travel bugs. She’s been down picking out light whatnots to wear in tropical countries.”
“Not only in the countries,” Della Street said, “but on shipboard, under the stars, and in the moonlight. Think, Chief, of sailing down below the equator, with the Southern Cross blazing overhead, the wind a warm caress on the skin, the wake of the boat streaming out behind in a white path. The scent of spices in the air, the hiss of water past the bow. Over on the right—”
“Starboard,” Drake interrupted. “By the time you’ve gone below the equator, you’ll know the nautical terms.”
“Okay,” she said, with a sweep of her arm, “over on the starboard is an island, the crests of the volcanic mountains silhouetted against the stars. Down lower against the water, where the palm trees fringe the lagoon behind the barrier reef, is a native village. And, from the deck of the ship you can hear the rhythmic throb of the native drums, the peculiar wail of primitive music—”
“No,” Mason interrupted, “you’re wrong again. The captain wouldn’t be standing in that close to an island after dark. He’d be out where there was plenty of sea room and—”
Della Street shook her head sadly. “Pardon me! My mistake! What we should talk about is murder — corpses with battered heads — clues, circumstantial evidence, bloodstained bullets, perjured testimony, and the beautiful things in life. Murderers who are corpses, corpses who are murderers. Now you, Paul Drake, get a load of this: Tomorrow the Chief and I are going to sail on the President Monroe on a round-the-world cruise. We have our staterooms all engaged, our tickets bought and paid for. There’s only one thing standing between us and the gangplank and that’s this Rita Swaine, who drifted in here with a lame canary and a hard luck story and got the Chief all tangled up in a mess. Now, you two get busy and straighten it out. But just remember that tomorrow—”
Drake, who had slid into his favorite position in the big leather chair, shook his head mournfully and said, “That’s what I came to tell you about, Perry. It’s all over except the shouting. You can sail any time you get ready.”