In 67 AD, after a devastating fire in Rome, Emperor Nero accuses Paul, Jesus' apostle, of being responsible and arrests him. Meanwhile, physician Luke arrives in Rome to find Paul, who is living with a Christian couple, Aquila and Priscilla. Despite the danger, Luke gains access to the prison and meets Paul, who agrees to tell his story before his execution. As Luke writes Paul's biography, he also details the early days of Christianity and the birth of the church.