An 8-year-old American boy wakes up alone in a rice paddy in a rural Chinese province with no idea how he got there. Details start to emerge when the boy, who calls himself Jacob, recalls that his hometown is Arcadia, and an Immigration agent, J. Martin Bellamy, takes him there. The home he claims as his own is occupied by a 60-year-old couple, Henry and Lucille Langston, who lost their son, Jacob, more than 30 years ago.
While they look different, young Jacob recognizes them as his parents. Lucille is overjoyed at the seeming miracle of her son's reappearance. Henry is reluctant to accept that Jacob is back. Those closest to the family want answers, including Sheriff Fred Langston, whose wife Barbara drowned 30 years ago while trying to save Jacob, and Fred's daughter, Maggie, a local doctor. Pastor Tom Hale seeks a spiritual reason for what's happening in his community. When things take an even more shocking turn, Maggie's life-long friend, Elaine Richards, finds herself drawn into Arcadia's growing mystery.
The Langstons, especially Sheriff Fred, are forced to confront secrets from their past they'd rather leave buried when Bellamy pushes to have Jacob's tomb exhumed. Maggie agrees to help Bellamy in his investigation, and Pastor Tom reaches out to Jacob, his childhood friend. The Richards family adjusts to Caleb's return, the second for Arcadia. But unlike Jacob, Caleb claims he has no memory of his death