Iowa farmer Ray Kinsella (played by Kevin Costner) hears a voice in his cornfield tell him, "If you build it, he will come." He interprets it as an instruction to build a baseball field on his farm, upon which appear the ghosts of Shoeless Joe Jackson and the other seven Chicago White Sox players banned from the game for throwing the 1919 World Series.
When the voices continue, Ray seeks out a reclusive author to help him understand the meaning of the messages and the purpose for his field.