The quest for the Holy Grail has consumed knights and crusaders, and has inspired legendary tales and Hollywood blockbusters. Could it be that the epic search is finally over? One church in Spain says they have found the sacred chalice, and that they have evidence to prove it, but some experts believe this is just the latest in a long line of false claims. Our team traces the extraordinary story behind this ultimate relic and uses forensic and historic analysis in an attempt to solve this 2,000-year mystery.