Preston Cole was alone under the banner of a thousand stars, gliding through the invisible currents of the sky. Nearing Mach two, the SR-71 Blackbird had long since outrun the thunder of its twin engines. There were no clouds that night, no moon, only starlight shining down on the desert plain below.

Inside the cockpit, awash in the pale glow of gauges and instrument panels, Cole looked out at the vast canopy of darkness that stretched over the horizon. He was the only fish in an infinite sea.

Seven years had passed since he last sat at the controls of such a machine, but once again surrounded by its elegant curves and sleek black skin, Cole felt right at home. There were, however, some changes: new instruments now lined the console in front of him, and there was no longer a rear seat behind him.

Instead of a copilot, there was now a seamless metallic sphere grafted inside the fusalage. From within its confines emanated a low, barely audible hum. Cole didn't hear it, but felt it in a pulsing vibration throughout the plane. He knew the source, and it was only then that he understood why NASA asked him to come back: every other qualified pilot turned down the job.