Inside his sealed tank on the top level of the enormous Dominic Class Heighliner, Steersman D’murr swam in orange spice gas.

Unaccountably troubled, and waiting for his Guild crew to complete the loading and unloading procedures, he felt time flow differently for him. His Heighliner had been in stationary orbit over Caladan longer than usual, due to an article that required special handling and a great deal of secrecy.

A combat pod. Interesting.

Normally, D’murr concerned himself with steering the great ship safely from one star system to another. It was his practice to ignore trivial details, human aspirations, since all the universe was his to hold and use.

Indulging in a moment of uncharacteristic curiosity, however, he tapped into the comsystem, flashed through records and transmissions, and eavesdropped on two Flight Auditors on a lower deck. Duke Leto Atreides had paid a substantial fee for this cargo, which required surreptitious delivery to Ix.

D’murr’s roundabout route through foldspace took him from world to world, to an endless parade of planets across the Imperium. On this run, one of his destinations was Ix, formerly a routine stopover for travelers from Caladan visiting their allies on the industrial planet. Now, though, much had changed.

Why are the Atreides going to Ix? And why now?

He listened to whispered conversations on the restricted Guild levels, gleaning additional information that the route supervisors would never reveal to outsiders because of strict neutrality agreements. For the Spacing Guild, this was business as usual. Two Atreides men would accompany the small craft to Ix, traveling under false documents. One was Prince Rhombur Vernius, in disguise.

D’murr absorbed the new information and found that his reactions were strange and extreme, even unbalanced. Elation? Fear? Rhombur. Unsettled, he consumed more of the melange in his tank, but instead of the expected sense of release, he felt as if the once-welcoming universe had become a dense forest of shadowy trees and indistinct paths.

Since becoming a Navigator, D’murr had never reacted this way to haunting memories, the detritus of his human past. The spice gas made his head ring, his brain crackle. He felt strangely out of synch, disoriented. He sensed large-scale, conflicting forces at work, threatening to rip the fabric of space. Out of desperation, he drank more deeply of melange.

D’murr decided the next foldspace leap would smooth the disruptive wrinkles around him. The journey always comforted him, restored his place in the cosmos. He inhaled more spice gas, felt it burn within him, hotter than usual.

After sending a terse, impatient inquiry to the Guild crew, he finally received word that the loading process had been completed. It is time. The hangar-bay doors and loading-dock ports swung closed.

Anxiously, D’murr began his preparations and high-order mental calculations. Envisioning a safe path required only a few moments, and the Holtzman-jump would take less than that.

D’murr never slept, spent most of his time in contemplation, drifting in his tank. Thinking back to his times as a young man, times as a human.

Ideally, Navigators should retain no such memories. Steersman Grodin, his superior on Junction, said it took longer for some candidates to shed their atavistic fetters. D’murr did not want his performance hindered. He had already achieved the rank of Steersman and looked forward to each journey through foldspace with great anticipation. And now, with some concern.

He worried that this continued flood of recollections and nostalgia might make him begin to revert to something different, something hideous and useless, something primitive and human. But he had evolved past that. All other states of existence, including humanity, were far beneath him.

But was he devolving now? Could that explain the troubling sensations? He had never felt so… peculiar. The spice gas around him seemed only to enhance his long-buried memories of Ix and the Grand Palais, of his parents, of the Navigation test that he had passed and his twin brother had failed.

A buzzer sounded inside the navigation chamber, and D’murr saw a ring of bright blue lights overhead. The signal to proceed.

But now I am no longer ready.

From the depths of his disturbance, D’murr felt a single, powerful surge of internal strength, as if he were desperately trying to raise himself from a sickbed. It was a distant call.

“C’tair,” he whispered.

Concealed beneath an abandoned Ixian school, C’tair Pilru stared at the blackened parts of his rogo transmission machine. Since it had been damaged more than two years ago when he’d made his last contact with his brother, he had found some replacement parts and repaired the device as much as he could. But the remaining silicate crystal rods were of questionable quality, scavenged from technological waste dumps.

In that last transmission, C’tair had begged his Navigator brother to find help for Ix. That thread of hope had frayed, until now. Rhombur must be on his way. The Prince had promised. Help would soon arrive.

With a flick of a whiplike tail, a small lizard scurried from one dark corner to another, disappearing into a pile of scrap parts. C’tair stared after the tiny reptile, seeing its gray-green body vanish. Before the Tleilaxu came, there had been no pests— no insects, lizards, or rats— in subterranean Ix.

The Tleilaxu brought other vermin in with them.

C’tair located the milky white rod he had set aside earlier. His last one. He turned it over in his hands, felt its coolness, and stared at a hairline crack along one side. Someday, if House Vernius rose in his lifetime, C’tair would have access to new components, and he could resume contact with his brother. As children, the twins had been remarkably close; they often completed each other’s sentences.

But now they were so far apart— in time, distance, and physical form. D’murr was probably parsecs away, sailing through foldspace. And even if C’tair could reconstruct the unorthodox transmitter, it might not be possible to reach him.

He clung to the silicate crystal rod like a filament of hope, and to his surprise it began to glow in his hands with a warm incandescence. The hairline crack brightened and seemed to disappear altogether.

A voice enveloped him, sounding like D’murr. “C’tair…” But it couldn’t possibly be. Looking around, he saw no one with him. He was alone in this dismal hiding place. A shudder coursed through his body, but the crystal rod grew warmer. And he heard more.

“I am about to fold space, my brother.” D’murr sounded as if he were speaking through thick liquid. “Ix is on my route and Prince Rhombur is aboard. He is coming to you.”

C’tair could not comprehend how his brother’s voice could possibly have reached him. I am not a rogo transmitter! I am only a person.

And yet… Prince Rhombur was coming!

In memory, D’murr was inside his twin’s mind long ago as C’tair picked through the smoldering rubble of an Ixian building destroyed in the initial Tleilaxu attack. How many years had it been? Twenty-one? Out of that rubble a hallucination of Davee Rogo had emerged, the crippled genius who had befriended the twins and shown them his wondrous inventions. Back in peaceful, halcyon times….

But that ghostly image had been transmitted by D’murr’s uncontrolled human side— a powerful force that had refused to succumb to the changes in his body and mind. D’murr had not been fully aware of what he had done, what concepts his subconscious had developed in tandem with his connection to his twin. Using information provided by the apparition, C’tair had then been able to build the cross-dimensional transmission device, enabling two-way conversation between a pair of very different, but genetically linked, life-forms.

Even then, D’murr’s subconscious mind had wanted to remain in contact with his home and memories.

Inside his tank, he now stopped moving his stunted arms and legs. Within the fraction of a second that he stood on the precipice of foldspace, he recalled the excruciating physical pain caused by each transmission with C’tair— as if his own Navigator persona had been fighting the human side, trying to subdue it.

But now he activated the Holtzman generator and lunged blindly between dimensions, taking the Heighliner with him.

Deep beneath the crust of Ix, C’tair held the flickering crystal rod until it grew ice-cold against his fingers, and D’murr’s voice faded. He shook off his surprised paralysis and called his brother’s name. No response came, only staticky, popping sounds. D’murr had sounded so strange, almost sick.

Suddenly, ringing through his skull, C’tair heard a wordless, primal scream in the very depths of his soul. His brother’s outcry.

And then nothing.