Transported to the 21st Century, Luke, the gospel writer, tells the story of his unexpected spiritual mission to help a young Lakota man on a vision quest. The Holy Spirit has sent him before Čhaŋté Little Hawk, in a cave of the Black Hills of South Dakota. Neither expects such a flesh-and-blood encounter spanning two millennia.

Accepting this role, Luke provides spiritual wisdom while learning about and affirming Lakota spirituality. Čhaŋté helps Luke overcome disorientation as he encounters the world two thousand years after his time.

Luke learns about many events, good and bad since Jesus walked the Earth. Concerning the complicated history between the Lakota and their conquerors, Luke provides some consolation, and together he and Čhaŋté confront the most difficult spiritual questions facing humankind. As they discuss the teachings of the Lakota holy man, Black Elk, Čhaŋté begins to see remarkable similarities between the two men.

The dominant culture around the Lakota reservations, however, is in turmoil. Americans feel rising mistrust toward each other, dividing themselves into tribes that sometimes see others as mortal enemies. Will this situation intrude on the personal relationship between Čhaŋté and Luke?