In the year AD 4544, a confluence of events shatters a spacecraft in the outer reaches of the solar system, hurling its lone commander, Samantha Hunter, through time and space deep into the past.

Meanwhile, in the near future, award-winning New York Times science editor Jonathan Elliot awakens in the middle of the night to an uninvited guest who appears to have materialized out of thin air. The strange visitor tells him a story so unbelievable that Jonathan feels compelled to write a speculative feature article for the Sunday edition. This midnight visit launches a nine-day whirlwind...