Drawing on the controversial "Bloodline" conspiracy that claims Jesus Christ and Mary Magdalene actually married and had children, director Bruce Burgess' documentary cuts to the heart of the matter by speaking with two alleged members of the Priority of Scion - a secret society rumored to have closely guarded the bloodline of Christ thought the centuries. In 1982, Christians around the world were shocked by a best-seller titled Holy Blood, Holy Grail, and though it was that book that is often credited with promulgating the "Bloodline" theory, it was author Dan Brown's 2003 novel The Da Vinci Code that propelled the theory to the forefront of contemporary religious debate. Could it be that the church has been covering up this secret for thousands of years? Now, in order to find out if there is any element of truth to the "Bloodline" theory, Burgess and his crew explore a wooden chest that may contain the greatest secret in the history of Christianity, discover a collection of handwritten letters penned by a late19th century priest who openly repudiates official Christian Doctrine, and contacts two supposed representatives of the Priority of Scion in hopes of finding the evidence that will solve a mystery 2,000 years in the making.