Klaus (Joseph Morgan) has the blood of the original vampires and werewolves flowing in his body. As time goes by, the unshakable prestige and power represented by his family gradually vanish. The evil Marcel (Charles Michael Davis) is gradually replacing the position of the Klaus family and ruling New Orleans with his tyranny and power. With their own purposes, Klaus and Elijah (Daniel Gillies) return to New Orleans, where they are not only waiting for their old enemy Marcel, but also a family of witches headed by Sofia (Daniella Pineda). In order to fight against the powerful Marcel, Klaus and others have to form an alliance with Sofia. However, this alliance is actually a double-edged sword. While attacking the enemy, it also threatens Klaus.