"No, Jake. I'm not kidding. I'm going to use it for a switch on the tired routine about an unknown killer menacing unknown victims. You know. Who's doing what to who and why." Lennox spilled his drink. "What's the matter?" "Nothing. Go on." "Here's the gimmick. You know about the dope habit. People start hitting heroin or cocaine and can't get off the hook. Well, the same thing happens with poison." "I don't believe it." "Some people acquire the poison habit. They eat arsenic for their health and--" "Their health!" "That's right. They take it in small doses so it isn't lethal and they build up a tolerance for it." "Why?" "They've got an idea it's good for them. For malaria. A tonic. An aphrodisiac. But dig this. Once they start they can't stop. It's habit-forming like dope. They've got to keep on eating poison the rest of their lives." "I'll be damned." "And they thrive on it, Jake. That's the truth." I waited a couple of minutes and then asked: "Why'd you throw a fit before?" He grimaced. "That line about an unknown killer and unknown victims. It was a little too close to home." "How?" "I'm in the same fix, Kitten." "You're an unknown killer?" "No. One of the victims." "This I got to hear." He shrugged. "Let's have another drink. I'll tell you about it if you swear to keep it quiet." I reached out with both arms and touched the crowd surrounding the bar. "On a stack of agency men." Jake snorted. We had another drink and he unloaded the letter story in a low voice, his eyes flashing angrily, his fists clenching and unclenching. He had a set of photostats in his pocket, but he wouldn't show them to me then ... not in Sabatini's with half the business leaning over our shoulders warning Romo to leave the garbage out of the old-fashioneds. When he was finished, Lennox looked at me expectantly. "You're a mystery writer, Kitten. How would you crack this one?" "When I plot 'em," I said, "I've got sense enough to give myself a gimmick to get out on. A left-handed man pulls matches from the left side of the book. The U. S. didn't mint any silver dollars from 1909 to 1921. All ticket punches have different designs ... and so on. Where's your gimmick?" "There isn't any I know of." "Then leave it to Fink. Smart cop, Fink. He'll find the gimmick." Lennox nodded. "But damn it, I can't sit on my credits and wait for the explosion Sunday. I've got to do something." "You're an amateur, Jake. Stay out of the act." "I've got a crazy feeling that everything's hanging on this one week. If I fight through the week, I'm safe. I've got to fight, Kitten." "You fight too much. Sit tight for a change and wait." "No. Damn it. No." He brooded, then burst out: "I've got an idea what to do." "What?" "While Fink's looking for the guy who's writing these letters...." "Could be a dame." "What?" "A dame. A doll. A tootsie. A--"