Documentary examining the medieval myth of the Philosopher’s Stone, a Holy Grail-type relic which supposedly held the key to alchemy and immortality. Many noted alchemists and adventurers searched obsessively for the artifact hoping to learn its powerful secrets, a quest which allegedly drove some to madness and others to celestial encounters. Today, the quest for the Philosopher’s Stone is merely thought of as a work of fiction from the pages of a Harry Potter novel. However, in the Middle Ages, the very real search for the Philosopher’s Stone was second only to that of the Holy Grail. It was believed that this mysterious stone, which one had to concoct from secret ingredients, could turn base metals into gold, and reveal the secrets of immortality. This fascinating documentary unearths the astonishing events surrounding this legendary stone, and the alchemists and adventurers who stopped at nothing in their search for this tantalising quarry. The programme also takes a wider look at medieval alchemy, and how this now obsolete science paved the way for modern scientists. The search for the Philosopher’s Stone presented a different challenge to that of the Holy Grail: while the latter was a geographical riddle, the Philosopher’s Stone was made of a variety of secret elements that an alchemist had to combine. Alchemists believed that gold was the most superior metal in the world, as it did not tarnish, rust or corrode. It was thought that the Philosopher’s Stone was made of something purer than gold itself, and that its presence next to something of a lesser metal could turn the inferior object into gold. Similarly, as gold was seen as perfection, human beings could draw from its elixir too, and turn from mortal (imperfect) to immortal (perfect).