Stan started running for the other side of the ship. There was the blasted port and then footsteps in the carbonized grass that had been flamed when the ship had landed. He ran quickly over the grass, following the footsteps, then glanced ahead into the city. He caught one brief glimpse of them. Two figures disappearing behind some rubble, running toward one of the side streets.... And the hoop that Stan knew was in an alley behind the Russian owned and operated department store in the Eastern sector. Stan dashed through the streets. They were two blocks ahead of him--Tanner and a girl, whom he was half pushing, half pulling. A beam flared above Stan's head and he ducked and zig-zagged from one side of the street to the other. The figures turned a corner and Stan fired one last, futile shot at them. When he finally turned into the street, there was nobody in sight--only the whirling black velvet of the hoop. He hesitated and then dove through it.... ... to a street he had seen once before. The Street of Lepers in Casablanca. The street was deserted--there were no signs of either Tanner or Avis. He walked slowly down the street, and then there was a rustling noise behind them. He whirled, just in time to see Tanner and Avis disappear into the hoop again. He ran and plunged in after them. It was going to be difficult, he thought. He would have to leave the vicinity of the hoop to look for them. And once his back was turned, they would be going through the hoop once more. * * * * * He caught a quick glimpse of Tanner in the deserted streets of Barcelona, Spain. He almost ran into the two in the empty streets of Shanghai. Madrid, Paris, Stuttgart, Leningrad, Los Angeles, Dallas--the cities flashed by like a deck of cards that was flicked past his eyes. The unending succession of black velvet hoops through which he moved like a man traveling through an infinity of dimensions.... And then the apartment in Bristol and Tanner was there, waiting for him. Simply standing against a table, waiting. Avis was in the far corner, her face frightened and drawn. Stan paused, eyeing the situation. "It's been quite a chase, hasn't it?" Tanner asked. Still the urbane Mr. Tanner, Stan thought. "I caught you, though, didn't I?" "It all depends on how you look at it. Perhaps _I've_ caught _you_." Tanner held an unfamiliar weapon in his hand. Stan looked at it curiously and then knew exactly what it was. Tanner had gotten hold of Avis' time pistol. He was going to kill him like William Clark had been killed. Tanner was going to age him a hundred years in a second. "Think you'll get away with it, Tanner?" "Why not? There's nobody to stop me!" How many times had he died in the last eight years? Stan wondered. How many times had his life been hanging by a thread, waiting for somebody to cut it? "_Stan! Duck!_"