The French capital of Paris has far more dead than living. Deep in its bowels lie millions of corpses. From the catacombs to the city's most famous cemeteries. What part have the dead played in the history of Paris? Have the lost souls revealed all of their secrets? To find out, we must investigate.

This is one of the darkest pages in the history of Paris. It mixes conspiracy and assassination attempt against the king, poisoning, black mass and child sacrifices. It's called the poison case. How to distinguish the truth from the legend? To find out, it is here in Paris that we must investigate.

The most mysterious chivalric order Paris has ever known. The Knights Templar. Theirs is a story of secrets and intrigue. Legends abound about these knights. If we want to discover the truth, we must investigate here, in Paris.

In the Middle Ages, the French capital of Paris had its fair share of centuries-old mysteries and secrets. Among them, was the era of the alchemists, who claimed they could turn base metals into gold? The best known of the alchemists was Nicolas Flamel. We will shed light on the arcana of alchemy.

This is the case of the rooms of the Palais Garnier, better known as the Paris Opera, which are said to be cursed. Numerous strange incidents have been recorded in them. To such an extent that many people claim they're the work of a ghost, the most famous ghost on earth: the Phantom of the Opera.

Can we communicate with spirits? A figure in the French capital of Paris maintained it was possible. His name was Allan Kardec, and what he achieved shook people's beliefs to the core. This is one of the city's most mysterious affairs. If we want to discover the truth, we must investigate.