Curt stared back across Mercury's lava-waste. The Prison Dome was well behind them now. He wished he could say how far ahead their objective lay, the little mountain-range that straddled half the planet. "Last chance," Curt told them grimly. "If either of you wants to change his mind, you've just enough oxygen to make it back! They may let you in again--if you want a month of solitary at the radite mines. What about you, Rikert?" The big man raised his head, laughed nastily. "Go back to that hell hole? I'd rather die a quick death out here. _You_ getting cold feet, Emmons?" Curt flashed darkly. He'd only made the suggestion for Kueelo's sake. "You, Kueelo? There's a chance of our missing Landreth. We've been delayed, and he said he'd wait only ten hours with the spaceship." The little Martian's face showed white in the darkness. His voice was soft, very soft and musical as always. "Thanks, Emmons. But I've waited years for a chance like this. If it were a million to one I'd still say go on." Curt nodded. Sure, he knew. Kueelo was a Martian political, an "irreconcilable," exiled to Mercury six years ago when Jal Tagar's government had taken over Mars. As to Rikert, Curt knew even less. The man had been sentenced for murder or space-piracy. It didn't matter now. What mattered was that these two knew even less about him. He wondered how long he'd stay alive if they learned his real status! DeHarries had taken into his confidence a mere half-dozen of his most trusted operatives. They were given widespread assignments. None knew what he would find, or where. And Curt's assignment, the Federation Prison, was toughest of all. Not even the Prison overseers knew his true identity! Curt worked with the hardened criminals of all planets, enduring the privations and hardships and awful radite rays. Gradually, Curt became one of the select group of prisoners who helped unload the supply ship which arrived twice a year. On its last arrival, just a few days ago, a crew member had slipped a folded note into Curt's hand! The message stated that _Landreth_ would be waiting on the darkside, and would take three men--any three. It set the time and the place. Landreth! Curt could scarcely believe his luck. That elusive pirate had disappeared, and was thought to be dead. Apparently not! What new scheme was he hatching now--and more important--did it have a bearing on the unseen forces which DeHarries felt were at work? Curt selected Rikert for the escape because the man was big and tough and could handle himself well in a showdown fight. Kueelo he selected for a different reason. It was partly sentiment--but more than that, Curt had a deep-rooted suspicion that Kueelo was more than an ordinary "political"! * * * * * Curt gave the signal, and they continued across the dark uncertain terrain. Jagged rock cut into their boots. Soon they were forced to circle wide around crevices large enough to swallow a man.