The story centers on Rachel Manners, a 35-year-old astrobiologist and member of an elite group of scientists chosen for one of the most critical missions ever conceived on Earth. She is now alone, orbiting an unknown planet, with only J.U.L.I.A., the space probe’s artificial intelligence, and Mobot, a large reconnaissance robot, for company.

After years of observation, the telescope Chandra 17 detects a solar system similar to our own. A signal of artificial origin is then found deep within it, and a massive space probe is built to meet and study extraterrestrial sentient life-forms.

The crew is carefully selected and trained, but everything goes terribly wrong. Rachel wakes from cryogenic sleep after decades and learns from the ship’s AI that she is the last surviving member of the probe’s crew.