Eight astronauts are on their way to Mars when Perseus disappears.

No distress call. No wreckage. No failing systems. One moment the mission is proceeding normally. The next, a spacecraft watched by millions is simply gone.

Within hours, grief turns into accusation. Governments demand answers. Mission controllers tear apart the final telemetry. Rival powers move assets toward Mars. The families of the missing crew discover how quickly private loss can become public property.

Then scientists find something they cannot explain.

Six-tenths of a second of impossible structure, recorded at almost the exact moment Perseus vanished.

It may be nothing. It may be evidence of a failure no one has imagined. Or it may mean that humanity was never as alone as it believed.

As secrecy spreads and nations begin acting on incomplete information, the disappearance acquires a name: the Vanishing of Perseus.

But finding out what happened may be less dangerous than deciding what to do when the silence finally answers.