And, since he knew that mommie was in the park, he could guess that the apartment was empty. All that went through my mind like a bolt of lightning. I said: "The apartment! Come on!" The Duke, looking a little puzzled, followed me to the door of 706. I put my ear against the door and listened. Nothing. Then I eased the key in and flung the door open. No one in the living room. I raced for the bedroom. No one in there, either, but the clothes closet door was shut. When I opened it, we saw a small, dark-haired girl lying naked and unconscious on the floor. Then there were noises from the front room. The sound of a door opening and closing, and the clatter of hurrying footsteps in the hall outside. We both turned and ran. In the hallway, we could hear the footsteps going down the stairwell. The slow elevator was out of the question. We took off down the stairs after him. He had a head start of about a floor and a half, and kept it all the way down. We saw the door swinging shut as we arrived in the foyer. Outside, we saw our man running toward the corner. I started to reach for my gun, but there were too many people around. I couldn't risk a shot. And then that amazing walking stick came into action again. The Duke took a few running steps forward and hurled it like a javelin, the heavy silver head forward. Robin Hood couldn't have done better with an arrow. When the silver knob hit the back of the running man's head, he fell forward to the sidewalk. He was still struggling to get up when we grabbed him. * * * * * [Illustration] The Duke and I were waiting for Dr. Brownlee when he came back from talking to Lawrence Nestor in his cell. "He's one of our zanies, all right," he said sadly. "A very sick man." "He's lucky he wasn't lynched," I said. "Did he tell you what happened?" Brownlee nodded. "Just about the way you had it figured. He had the little girl's clothes off when her mother came back. He heard her putting her key in the door, so he grabbed Shirley and dragged her into the closet with him. The mother didn't search the place at all; she just went through the main rooms, called her daughter's name a few times and then left." "That's what threw us off at first," I said. "We both accepted Mrs. Ebbermann's word that Shirley wasn't in the apartment. Then I realized that she wouldn't have taken time to look in all the closets. Why should she? As far as she knew, there wasn't any reason for Shirley to hide from her." "It's a good thing Mrs. Ebbermann did come back." Dr. Brownlee said. "That was the only thing that saved the girl from rape and death. Nestor was so unnerved that he just left her in the closet, still unconscious from the blow he'd given her.