Bloodline investigates the conspiracy theory made popular by the movie "The Da Vinci Code" which claims that Jesus married Mary Magdalene and had children. In this documentary, filmmakers Bruce Burgess and Rene Barnett research the theory as well as the secret society linked to the conspiracy, the Priory of Sion. Burgess and Barnett spent three years making the film, following clues and meeting with other researchers. One such researcher is Ben Hammott, an English adventurer and treasure hunter. In his search for hidden treasures, Hammott finds several clues hidden in a large mural on a church wall. Later Hammot finds handwritten papers signed by a priest. In the documents the priest indicates that "the resurrection of Jesus was a trick". Along their journey, the filmmakers locate a remote mountain tomb, a mummified corpse wrapped in a shroud, wooden chests filled with treasures and a cache of relics from ancient Jerusalem.