Apophis was a villain in the Stargate SG1 TV series. He belonged to the alien race of the Goa-uld. He was played by Peter Williams and Dion Johnstone later in the series.
In the aftermath following the death of Ra, Apophis' power significantly increased during 1997, along with the knowledge of his existence. In order to find a new mate, he used the Stargate on Chulak to search various planets for appropriate females, including Earth and Abydos. Apophis arrived on Earth before the Stargate was set to be buried and kidnapped a female United States Air Force Senior Airman. Despite resistance by other Airmen, he was not stopped and was able to return to Chulak. He later arrived at Abydos, while Colonel Jack O'Neill's team was present and kidnapped Sha're and Skaara.
With his job done, he had his mate, a symbiote, check the females and kill them if they weren't adequate. Apophis killed the female Airman, but accepted Sha're as his new mate. Arriving at a village in Chulak, he revealed the implanted Sha're to a group of individuals, which included SG-1. Apophis ordered SG-1 taken prisoner, and they were thrown into a large cell with other Abydonians. He returned to the cell and ordered his Jaffa servants to locate children to select the "Children of the gods". Once the children were selected, Apophis ordered the other prisoners executed and promptly left to go to the Stargate. The execution was foiled by O'Neill and Apophis' First Prime Teal'c and they, along with the rest of SG-1 and the Abydonians, attempted to stop Apophis from leaving with Skaara. Their attempts failed and Apophis and his group left to an unknown planet.
In revenge for the actions of SG-1 and SG-2, Apophis had a number of his Jaffa attempt to invade Stargate Command. However, his attempts were faltered by the SGC's Stargate Iris. Apophis eventually stopped his assault after a number of attempted invasions. (SG1: "The Enemy Within", "Emancipation")
Continuing his search for the cloakable Fenri on a planet occupied by the Nox, Apophis attempted to capture a Fenri with three other Jaffa guards, including Shak'l. At the same time, SG-1 was investigating the mystical creature too. Apophis encountered SG-1, who had ambushed him, but he was able to activate his personal force field within his hand device before he could be stunned. Using one of his guards' staff weapons, he was able to kill all members of SG-1, minus Teal'c. The Nox took SG-1, along with an injured Shak'l and healed them. When Shak'l escaped, he alerted Apophis to the magical powers of the Nox, which prompted an attack. However, Apophis' attack was foiled by a revived SG-1. Jack O'Neill was ready to stun Apophis, but before he could, the Nox transported Apophis through the Stargate.Because of the problems the Tau'ri were causing the Goa'uld, Apophis, with his son Klorel, took two ha'taks in a campaign to conquer Earth. SG-1, however, had already arrived on a Stargate being carried in Klorel's mothership, and managed to rig the vessel to explode and incapacitate Klorel. Bra'tac, Apophis' former First Prime, also helped SG-1, by directing Klorel's mothership to move closer to Apophis', and damaging the Pel'tac's controls. Unable to save his ship, Apophis and Klorel ringed over to Klorel's mothership and used the Stargate to escape. But the damage to Apophis was incalculable. (SG1: "The Serpent's Lair")
Because of the loss of two motherships and most of his Serpent Guards, Apophis' standing among the System Lords was considerably weakened. Apophis attempted to take revenge on Teal'c by brainwashing his son Rya'c and using him to infect Earth with a deadly plague, though the SGC stopped him. He also impregnated Sha're, host of Amonet, with the hopes of using the child as a future host. However, Daniel Jackson and Teal'c thwarted his efforts, feeding him misinformation that Heru'ur took the child.Within a year, Apophis' forces were nearly depleted, suffering losses to both Heru'ur and Sokar. Fleeing from Sokar's forces, Apophis demanded sanctuary among the Tau'ri, at the very least hoping to kill the Tau'ri with him. However, the Tau'ri soon turned Apophis over to Sokar, who sent him to Ne'tu. Apophis managed to assume the guise of Na'onak, First Prime of Bynarr, Lord of Ne'tu. However, at some point his face was horribly disfigured on one side, presumably from torture and he took to wearing a sort of mask over that side after his escape.
When SG-1 and the Tok'ra Martouf arrived hoping to rescue Jacob Carter, Apophis killed Bynarr, and incited a rebellion. He tortured SG-1, trying to learn information to make Sokar spare his life. he required information on the iris codes, and how to contact the Asgard. While he greatly enjoyed torturing SG-1, all he learned was that the Tok'ra were based on Entac. Planning to kill Sokar once he was in his presence, Apophis ringed aboard Sokar's mothership. However, Sokar had already conquered Entac, and there were no Tok'ra there. Sokar ordered Apophis to be killed, but soon Netu's core began to destabilize. Apophis killed Sokar's guards and ringed to Delmak, Sokar's homeworld. Sokar was killed when Ne'tu's explosion destroyed his ship. There, he claimed that he had killed Sokar, and took Sokar's forces for his own.
Less than a year later, the SGC learned of Apophis' survival, after he launched an attack on Chulak, searching for the Harcesis, and later launched an attack on Kheb. He also built a new flagship, more powerful than the standard Ha'tak, and began to build a new type of mothership. The later was destroyed when SG-1 sabotaged the construction facility.Apophis later came close to an alliance with Heru'ur, but the Tok'ra and SG-1 were able to sabotage it, hoping to start a war between the two and decimating their power. However, Apophis had brought a cloaked fleet with him, and was able to destroy Heru'ur's mothership, killing him. Absorbing Heru'ur's forces into his own, Apophis was easily the most powerful System Lord within the Goa'uld Empire.
With his fleet on the way to attack the Tok'ra base on Vorash, Samantha and Jacob Carter devised a bold trap: they intended to cause Vorash's sun to go supernova, hoping to destroy most of Apophis' fleet and possibly even Apophis himself. The plan worked, but Apophis survived, capturing Teal'c in the process. Apophis' mothership and a ha'tak that SG-1 had acquired after they had killed Cronus was thrown to another galaxy, one which the Replicators were in. The Replicators destroyed Apophis' mothership, though Apophis was able to escape along with a few Jaffa bodyguards and Teal'c, who had been brainwashed into believing he was his First Prime. Apophis and his forces were able to take over the ha'tak, but the Replicators had managed to sneak aboard. The Replicators took control of the Ha'tak, flying to Delmak at incredible Apophis dies speeds. Though SG-1 and Jacob were able to escape, taking Teal'c with them, Apophis was trapped in the pel'tac. SG-1 was able to disable the sublight drives, causing an uncontrolled re-entry into Delmak. Apophis was killed in the crash.
His death, following the death of Cronus a few days earlier, caused the System Lords to enter into a war that the Tok'ra hoped would last for years. However, it helped Tanith and Zipacna become formidable players in the "new order" forged. Worse, it also accelerated events which resulted in the return of Anubis.