"Let's," she smiled. "Here's to a fine old professor, who invented a time machine and kindly let me kill him and take it away. Here's to a policeman's nightmare--the perfect murder." They drank. Smith got to his feet then and put the glass down. "Well, I've got to go now, I--" He saw the blank look of astonishment on her face. Her mouth had dropped open and her eyes were wide, staring. But they weren't looking at him--they were looking _behind_ him. And then he heard the polite cough. Smith spun around. He stared in amazement at the figure of a man standing there. A man clad in a strange shimmering metallic uniform. The man held an odd-looking weapon in his hand. He was smiling. "Mr. Smith, I believe?" Smith nodded automatically. "Yes, but who--" "--am I?" the stranger completed the sentence for him. "It's quite simple. I'm Inspector Graevod, homicide. I'm arresting you for murder." Smith shook his head dully. "But that's impossible. There's no murder--no body.... Where did you come from?" The shimmering man smiled pleasantly. "Oh but there is a body. Matter of fact there are quite a few. We've had quite a bit of difficulty in tracing you down. I've come all the way from 2035 to find you." He turned his eyes to the woman. "As an accessory to the fact you are also under arrest. Come along, both of you." He pointed the strange weapon at them and a silver radiance swept from it to envelope their bodies. But only for a moment. Then they were gone....