The marks correspond to the places where Christ was nailed to the cross and cut with a spear by his killers. They appear suddenly and may leave the same way, or linger for decades. They are stigmata, and they are among the most puzzling of all unexplained phenomenon.

STIGMATA: MARKED FOR LIFE chronicles the most famous of the over 300 claimed occurrences of stigmata through the ages. Here is the story of St. Francis of Assisi, the first stigmatic, on whom the wounds appeared in 1224; of Padre Pio, an Italian friar who is said to have bled for fifty years until his death in 1968; of Theresa Neumann, who believers said survived only on the Eucharist for 35 years. In each of these cases, experts like Ted Harrison, the author of "Stigmata: A Medieval Phenomenon," and Neuro-Psychologist Dr. Marco Magnelli, examine the historical records in search of clues about what lies behind this extraordinary phenomenon.

Are they acts of God? Have these people really been touched? Or are they simply desperate attempts for attention? STIGMATA: MARKED FOR LIFE explores every side of an issue that blends faith, medicine and myth.

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