Heptarian is the secondary antagonist in BBC series Atlantis. He is one of Atlantis's greatest warriors, the Nephew of Pasiphae and the servant of the God Posidon. He is secretly conspring with the queen to seize the throne and him to marry Minos daughter Ariadne.
Jason first met Heptarian when an old man cart collapsed, blocking Heptarian and his men's way. Angered, rather than walking arround Heptarian turned on the old man and demanded he move it. When the man tried to explain he needed time Heptarian struck him and continued to demand, when the man didn't fast enough Heptarian struck him again. Unable to watch Jason interveaned and knocked Heptarian down. Heptarian thus had them arrested and then lied in the court, causing Jason and his friends to be sentanced to the Bull Court, a contest which was practically death by trial. He then conspired with Pasiphae to have Jason killed, as Pasiphae had noticed Jason had earned Ariadne's affection, something which interfered with her plan. However the plan failed, Jason and friends survived the bull leaping and thus Minos set them free. And Ariande snubbed him and instead went to temple to pray rather than spend time him.
Later after Pasiphae realised that Therus was still alive, she ordered Heptarian to take part of Atlantis army and kill him. Heptarian was intially unwilling as Therus was the Kings son, however Pasiphae talked him into it. However upon arriving he failed his task, as Therus (along with Jason and the others who had been delivering a message from Ariadne to him) escaped. Upon returning he was given a sevear scolding by Pasiphae, and was tasked to watch Ariadne, knowing she would sneak out to visit her brother. However Ariadne outsmarted him by switching places with her servant Korinna and managed to escape.
Following Minos officially announcing the betrothal of Ariadne and Heptarian, he prepared to compete in the Pankration (A contest to first blood between two opponents) that was being held to celebrate, following years of training he planned to win. However he worried about Ariadne's unwillingness to marry him. In the Pankration he faced many sutible warriors and managed to best them all, however his willingness to fight dirty and actually kill his opponents started to turn the crowd against him. Pasiphae called him out on this, pointing that if he was to become king, he had to have crowds support and act honourably. Finally the finale match came down between Jason and Heptarian. The two fought, and although the stronger of the two, Jason managed to finally overpower Heptarian, however knowing that if he won, Pasiphae would have them assissinated, Jason threw the fight. Heptarian grabbed the knife and went to kill Jason, however realising doing so would permantly turn everyone against him, he instead was forced to do the honourable thing and simply give Jason a slight nick. Heptarian won, but Jasons braverly inspired Ariadne to convince her father that there union wasn't supported by the gods, thus Minos called off the marriage. Heptarian left trying to convince the king to reconsider.
Heptarian was later informed of the sightings of a monster (really Jason under a curse) in the town, dismissing them he never the less asked Ramos to keep him informed of any developments. Later Ramos reported that a patrol of guards had seen and encountered the creature forcing them to flee. As such Heptarian summoned the garrison and led a patrol of guards, however he failed to find the creature, as Hercules and Pythagerous had already managed to capture Jason.
Later upon Minos being near death, Pasiphae criticised him for failing to succeed in marrying Ariadne as when Minos died, the throne would go to her, not Pasiphae. Upon hearing of a intruder who tried to kill the queen, Heptarian led a squadron of guards searching the palace for him, he asked Ariadne if she had seen anyone, but Ariadne lied and said she hadn't. Pasiphae, upon later discovering that Ariadne hid the intruder (who was Jason) Heptarian fetched Ariadne to take her before the court on charge of treason.
However at the exercution, Jason interveaned and with the help of his friends saved Ariadne. Heptarian led the guards after them. He confronted Ramos in the sewers, Ramos refused to stand aside. Heptatarian set two soldiers on him, waiting till he was to tired to fight him. Emerging he admited Ramos was a honourable man, and said the others could learn a lot from him, before killing him. He along with with Pasiphae and a large number of soldiers, went searching for Ariadne. He managed to find her trail and arrived at the miles were they were hiding. Leading the forces in, he was ambushed by the Leapers who lived in them, and had alingned with Jason. He killed a few, but was ambushed and gravely injured. However Heptarian survived and chased after Jason. Tracking him down he tried to kill him, Jason grabbed his own sword and took him on. Although both men where injured the fight was intense, Heptarian consumed with hatred. Heptarian managed to overpower Jason, but Jason managed to regain the upper hand, and stabbed him through the chest killing him.