D’murr, a voice said in the back of his awareness. D’murr . . .

Within the sealed navigation chamber atop his Heighliner, D’murr swam in spice gas, kicking his webbed feet. Orange eddies swirled around him. In his navigation trance, all star systems and planets were a grand tapestry, and he could travel along any thread he chose. He derived supreme pleasure from entering the womb of the universe and conquering its mysteries.

It was so peaceful in deep, open space. The brightness of suns came and went . . . a vast, eternal night dotted with tiny points of illumination.

D’murr performed the higher-order mental calculations required to foresee a safe course through any star system. He guided the immense ship through the limitless void. He could encompass the reaches of the universe and transport passengers and freight to any place he desired. He saw the future and conformed to it.

Because of the outstanding abilities he had demonstrated, D’murr was among only a few mutated humans who had risen through the Navigators’ ranks so swiftly. Human. The word was little more than a lingering memory for him.

His emotions— strange detritus from his original physical form— swung him in a way he had not expected. In the seventeen Standard Years he’d spent growing up on Ix with his twin brother C’tair, he had not possessed the time, wisdom, or desire to understand what it meant to be human.

And for the past dozen years, admittedly by his own choice, he’d been removed from that dubious reality and vaulted into another existence, part dream, part nightmare. Certainly his new appearance could frighten any man who was unprepared for the sight.

But the advantages, the reasons he had joined the Guild in the first place, more than compensated for that. He experienced cosmic beauty unknown to other life-forms: What they could only imagine, he actually knew.

Why had the Spacing Guild accepted him at all? Very few outsiders were admitted to the elite corps; the Guild favored their own Navigator candidates— those born in space to Guild employees and loyalists, some of whom had never walked upon solid ground.

Am I only an experiment, a freak among freaks? Sometimes, with all the contemplative time on a great voyage, D’murr’s mind wandered. Am I being tested at this very moment by some means that can scan my aberrant thoughts? Whenever the wild awareness of his previous human self came over him, D’murr felt as if he were standing on the edge of a precipice, deciding whether or not to leap into the void. The Guild is always watching.

While floating in the navigation chamber, he journeyed among the remnants of his emotions. An unusual sense of melancholy enveloped him. He had sacrificed so much to become what he was. He could never land on any planet unless he emerged in a wheeled and enclosed tank of spice gas. . . .

He concentrated hard, drove his thoughts back into line. If he allowed the human self to become too strong, D’murr might send the Heighliner reeling off course.

“D’murr,” the nagging voice said again, like the throbbing pain of a mounting headache. “D’murr . . .”

He ignored it. He tried to convince himself that such thoughts and regrets must be common for Navigators, that others experienced them as often as he did. But why hadn’t the instructors warned him?

I am strong. I can overcome this.

On a routine flight to the Bene Gesserit world of Wallach IX, he piloted one of the last Heighliners constructed by Ixians, before the Tleilaxu took over and reverted to an earlier, less efficient design. Mentally he reviewed the passenger list, seeing the words imaged on the walls of his navigation tank.

A Duke was aboard— Leto Atreides. And his friend Rhombur Vernius, exiled heir to the lost fortunes of Ix. Familiar faces and memories . . .

A lifetime ago, D’murr had been introduced to young Leto in the Grand Palais. Navigators overheard snippets of Imperial news and could eavesdrop on business conducted over the communication channels, but they paid little attention to petty matters. This Duke had won a Trial by Forfeiture, a monumental act that had granted him respect throughout the Imperium.

Why would Duke Leto be going to Wallach IX? And why did he bring the Ixian refugee?

The distant, crackling voice cut in again: “D’murr . . . answer me . . .”

With sudden clarity he realized it was a manifestation of his former life. Loyal, kind C’tair attempting to stay in touch, though for months D’murr had been unable to reply. Perhaps it was a distortion caused by the continuing evolution of his brain, widening the gulf between himself and his brother.

The atrophied vocal cords of a Navigator could still utter words, but the mouth was primarily used to consume more and more melange. The mind-expansion of the spice trance pushed away D’murr’s former life and contacts. He could no longer experience love, except as a flickering memory. He could never again touch a human being. . . .

With one of his stubby webbed hands he withdrew a concentrated melange pill from a container and popped it into his tiny mouth, increasing the flow of spice through his system. His mind floated a little, but not enough to dull the pain of the past, and of the attempted mental contact. This time his emotions were too strong to overcome.

His brother finally stopped calling to him, but he would return soon. He always did.

Now, the only sound D’murr heard was the steady hiss of gas entering the chamber. Melange, melange. It continued to pour into him, filling his senses completely. He had no individuality left, could barely tolerate speaking to his own brother anymore.

He could only listen, and remember. . . .