Her small, strong hands clenched together. "If only you could have taken him, as you planned. If we could have taken him back, it would be complete proof of what Vannevan's doing here." Birrel couldn't get this at all. He was bewildered, all his previous assumptions and those of Connor completely upset. They had had it figured out, they thought. The dead man was a spy from another world. He would have colleagues, a group who had come here to search out Earth's most potent defense secrets, with some deadly purpose surely. Birrel's job, his imposture, was to lead to the others. But--it seemed now that these secret ones, this Kara and Holmer, themselves had enemies. The dead man, Rett, had been trailing one. An Irrian. Who were the Irrians? Who was Vannevan, and what was _he_ up to? A sense of nightmare unreality suddenly swept Birrel. Their car was crossing lower Times Square. The blaze of lights, the after-show crowds, the winking signs--all were so utterly normal. And here, in the midst of it, he rode with a man and woman of a far world, speaking their language, talking tensely of things he didn't even understand. Birrel felt a frantic desire to rip the door open and plunge out of the car, to run and lose himself in the cheerful crowds. He couldn't. He'd taken the job and he had to go through with it--to find out where their base was, to find out what threat they represented. "But I have to play it alone," he thought, with sinking heart. Connor and Paley and the rest, who had planned so carefully to follow them, had never foreseen that stunning force that had struck. Birrel became aware that they had crossed town and were running through the Lincoln Tunnel. In a few minutes they were on a main highway, heading north. How long could he keep up this imposture? How long till he made some slip, some blunder-- Holmer, his voice quiet but with a sudden edge to it, said, "There's a car following us. I wasn't sure till we got through the Tunnel." With sudden reaction, Birrel's hopes leaped. Then Connor and the others had come to in time to follow? Yet it hardly seemed possible.... "_Vannevan!_" Kara's exclamation was so fierce that it startled him. "It can't be anybody else," Holmer grimly agreed. "That newspaper story about the captured spy--it drew _him_ to the prison too, it seems." Whoever Vannevan might be, Birrel thought, it was evident that these two hated and feared him like the devil. Holmer gripped the wheel tighter, and the car suddenly lunged faster. He said, without turning, "You know what it means. The Irrians know now that we followed them to Earth. Hold on, we have to lose them!" As by a lightning-flash, the shocking truth was abruptly revealed to Birrel. _Two_ groups of secret agents, bitterly hostile to each other, playing a vast and deadly game against each other, were on the unsuspecting Earth! CHAPTER IV