Applewhite (Unabridged‪)‬

In 1997, a religious cult named Heaven's Gate believed a comet passing through the solar system concealed a spaceship that would teleport its members to a level beyond human. More than 2000 years later, the comet has returned. 

In a future where most of Earth's information has been lost, Heaven's Gate has been resurrected. Few take the cult's beliefs seriously until a mysterious man appears claiming to be from the 20th century.