Sahjhan's History
Uncorporealization
Sahjhan was one of a race of demons known as the Granok, who thrived on chaos and violence. Deciding that the Granoks were too chaotic and unpredictable, Mesektet and Wolfram & Hart used a spell to render them, including Sahjhan, incorporeal. Though it was meant to prevent the Granoks from interacting with their environment, Sahjhan developed the power to travel through time and dimensions, earning the nickname "Timeshifter."
Working with Holtz
Eventually, after the birth of Angel's son Connor, Sahjhan travelled back to the 18th century to recruit Daniel Holtz, a vampire hunter whose life was destroyed by Angelus and Darla, and made a bargain with him to take him into the future and have another chance at revenge, claiming to despise Angel himself; in reality, however, Sahjhan intended to have Connor killed because of a prophecy foretold in the Nyazian Scrolls, which claimed that Connor (the one fathered by the vampire with a soul) would grow to adulthood and kill him. As part of his plan, Sahjhan traveled back in time and altered the parts of the prophecy concerning his death to read "the father will kill the son," leading Angel's friend and team-mate, Wesley Wyndam-Pryce, to believe that Angel would kill Connor.
However, Sahjhan grew impatient with Holtz when, instead of simply killing Connor, he laid out an elaborate scheme to kidnap Connor to get revenge on Angel once and for all. Faced with this, Sahjhan turned to Lilah Morgan for help, who spiked Angel's supply of pig's blood with samples of Connor's blood she stole from the hospital, causing Angel to become increasingly violent. Out of fear for the baby's safety, Wesley made a deal with Holtz and kidnapped Connor, only to have his throat slit by Holtz's right-hand man, Justine Cooper.
In the midst of a four-way confrontation between Sahjhan, Wolfram & Hart, Holtz's forces, and Angel, Sahjhan tore open a rift to the dimension of Quor'toth, threatening to suck everyone into it. However, Holtz took advantage of this to jump into the rift himself, taking Connor with him. Deciding that Connor was as good as dead in Quor'toth, Sahjhan closed the rift behind them.
Recorporealization and imprisonment
Enraged and grief-stricken, Angel used a spell to recorporealize Sahjhan, intending to either force him to open another rift to Quor'toth so he could save his son or kill him out of revenge for Connor's disappearance. In the ensuing confrontation, Sahjhan revealed his plans and that the prophecy that led to the kidnapping was faked by him before taking on Angel. Sahjhan quickly proved too powerful for Angel and his allies to handle, and was just about to stake Angel when Justine arrived and used a Resikhian urn to imprison Sahjhan out of revenge for Holtz's disappearance.
Return and death
At some point after Sahjhan's imprisonment, his old enemy Cyvus Vail got his hands on the urn imprisoning him. Two years later, wanting to put his affairs in order and worried that Sahjhan would break free and kill him, Vail made a now-normal Connor aware of his powers and threatened to restore his memories if he didn't kill Sahjhan. Angel reluctantly agreed and at Vail's mansion, Connor was locked in a room with the urn and several weapons. Connor released Sahjhan who joked with him before he realized who he was.
Sahjhan attacked Connor, who was no match for him as with his false memories he lacked any real fighting skills. Sahjhan nearly strangled Connor to death before Wesley shattered Vail's Orlon Window, restoring Connor's true memories. With his fighting skills returned to him, Connor grabbed an axe and gained the upper hand by stabbing Sahjhan in the stomach. While he was stunned, Connor decapitated Sahjhan, killing the demon and fulfilling the prophecy.
