This series that explores the mysterious case of Natalia Grace, a young woman who was adopted from Ukraine by an American couple. The couple initially believed that Natalia was a 6-year-old orphan with a rare bone growth disorder, but they soon began to suspect that she was actually a much older adult. The docuseries follows the Barnetts as they try to unravel the mystery of Natalia's true identity and uncover the truth about her past.