The Empire and the North
The world of The Witcher is a dangerous place. In the south, the massive Nilfgaardian Empire presses forward in an attempt to expand its empire to the north. Only a handful of kingdoms remain independent of the Nilfgaard's aggressive expansion: Temeria, Aedirn, Redania, Kaedwen and Kovir. Non-humans - such as elves, dwarves and halflings - suffer bigotry and violence from humans and the land is terrorized by a host of vicious creatures.
Though an instability exists between non-human and humans throughout the unnamed continent, a modicum of control exists in the fight against monsters. These warriors are the Witchers.
Geralt of Rivia
The central figure in CD Projekt Red's video game adaptation series is Geralt, part of a dwindling group of hunters known as Witchers.
Witchers are genetically mutated humans who undergo years of special training and are imbued with supernatural abilities thanks to various potions and elixirs. Their development, which the universes lore states begins at an early age, is for the specific purpose of hunting and slaying dangerous monsters that terrorize the land.
Secrets of the Witcher order
The first game in CD Projekt RED's series begins years after the conclusion of the Witcher novel saga as Geralt is discovered in a forest with no memory of his previous life.
Geralt struggles with amnesia, unsure of his past. As he attempts to piece together his memories within the walls of Kaer Morhen, the last remaining Witcher stronghold in the world and home to the remaining few of his kind, the fortress is attacked by a group known as the Salamandra. In the ensuing conflict, an assassin known as the Professor and a Salamandra mage named Azar Javed escape with the secrets of Witcher mutation, which had been sealed by the Witcher Order for centuries.
Note: The Witcher series author and creator, Andrzej Sapkowski, has stated that CD Projekt REDs video game series is not canonical.
The Flaming Rose vs the Squirrels
On his way south to Temeria's capitol city Vizima in search of the Salamandra, Geralt befriends a dwarf named Zoltan and a child who appears to have powerful magical abilities named Alvin. The region is in turmoil, Geralt learns. Vizima is under quarantine and two militia groups - the human Order of the Flaming Roses and the Scoia'tael (a group of guerrillas made up of non-humans, such as elves and dwarves) - are embroiled in a growing conflict.
After being taken prisoner before entering the Vizima city gates, Geralt is offered his freedom in exchange for defeating a creature that stalks the sewers under the city. Underground, Geralt meets Siegfried, a knight who aids in his quest to defeat the menace and offers him advice in his search for information regarding the Salamandra. In his quest to uncover the group's plan, Geralt comes face-to-face with the Professor and Azar Javed, but the pair escape after Geralt is knocked unconscious.
The princess plot
Geralt regains consciousness in the personal quarters of the powerful mage Triss Merigold, who had been among those that nursed him back to health at Kaer Morhen. The mage works to restore his memories, but cannot unlock his mind. As Geralt uncovers Salamandra bases within the walls of Vizima, the extent of Alvin's powers become more clear. The boy has visions of humanitys destruction and is eventually revealed to be a Source, a person born with innate magical abilities rather than earning those gifts through training or elixirs.
In Vizima, Geralt greets Princess Adda - daughter of the King Foltest, ruler of Temeria - and it's revealed that the Witcher had once cured her of a disease that was transforming her into a feral beast many years ago. Eventually Geralt discovers the Princess is working with the Salamandra and is once again confronted by the mage Javed and the hired killer known as the Professor. In the encounter Geralt manages to kill the assassin, but Javed flees. To protect her role in the Salamandra plot, Princess Adda calls for Geralt's arrest, but Triss manages to teleport Geralt away to safety.
Alvin and the amulet
In the village of Murky Waters, Alvin's visions continue to disturb him. Geralt and his friend Dandelion the Bard care for the boy. To help suppress his magical abilities and nightmares, Geralt gives Alvin a pendant sent to him by Triss.
The conflict between the Flaming Rose and the Scoia'tael (also known as the Squirrels) expands to the region, giving players the ability to remain neutral in the battle or choose the side of either the knights of the Flaming Rose or the non-human Squirrels. The conflict scares Alvin and the young boy mysteriously disappears in a flash, never to be seen again.
Grand Master of the Order
The civil war between the Flaming Roses and the Squirrels reaches its apex, with all non-humans within the region joining the ranks of the Scoia'tael. Princess Adda once again begins to transform and King Foltest pleas for Geralt's assistance. Geralt can decide to either kill the Princess or cure her once and for all. Regardless of Geralt's decision, King Foltest helps the Witcher locate Azar Javed. Geralt finds and kills the mage and learns that it was Jacques de Aldersberg, the Grand Master of the Order of the Flaming Rose, that was responsible for the attack on Kaer Morhen.
Geralt learns that Jacques de Aldersberg's plan is to use the secrets from the Witcher Order to create an army of mutant soldiers to protect humanity from an apocalypse. During a battle with Jacques, who is revealed to be a Source, Geralt and the Grand Master are teleported into the potential future, a decimated world that resembles the destruction of humanity prophesied by Alvin's visions. After killing the Grand Master, Geralt discovers Jacques carries a dimeritium pendant similar to the one given to Alvin by Geralt, though it has been ravaged by time. Though it has never been confirmed within the game's narrative or by CD Projekt RED, popular fan theory (and some in-game speculation) surmises that Alvin disappeared through time and grew up to become Jacques de Aldersberg.
Geralt's quest doesn't unlock his memories, but he is given a pretty penny for his role in quelling the rebellion of the Order. King Foltest offers his thanks and Geralt makes his way toward "a new beginning." Before leaving the kingdom, however, Foltest is attacked and Geralt steps in to save his life. After killing the would-be assassin, Geralt discovers the kingslayer is also a Witcher.
The Witcher 2: Assassins of Kings
Geralt of Rivia is now employed by King Foltest, assigned to offer advice and protect him from danger, alongside Triss Merigold. Geralt's past is still hazy, but pieces of it return to him over time. Geralt helps the King rescue his illegitimate children from a former lover, but an assassin - who is later revealed to be a Witcher - infiltrates the stronghold housing the children and kills the King. Geralt is immediately suspected of the crime, and is arrested for regicide.
Geralt convinces Temerian Special Forces commander Vernon Roche that another is responsible for the King's death during interrogation. Roche offers Geralt the opportunity to hunt down the true king slayer and frees him. The two escape together and, along with Triss, follow the true assassin's trail to the city of Flotsam.
The rebel elf
Once the trio land in Flotsam, they are ambushed by rebel elf Iorveth. It is revealed that Iorveth is working with the Witcher responsible for the death of King Foltest as well as the death of the king from the neighboring region of Aedirn.
Once Geralt, Triss and Roche make their way to the town square, Geralt reunites with (and saves from hanging) his old friends Zoltan and Dandelion. While in town Geralt defeats a giant monster threatening the town's economy and learns that the Witcher kingslayer intends to betray Iorveth. Geralt manages to convince Iorveth that his assassin ally is untrustworthy as Roche arrives with an armed force to stamp out the rebel threat. Geralt eventually confronts the Witcher assassin, named Letho, but the kingslayer escapes and takes Triss Merigold as his hostage.
From here players choose to side with Iorveth or Roche, altering the path toward the game's ending.
The story following Iorveth
If Geralt sides with the rebel elf the two sail to Aedirn in pursuit of Letho. While there, the two are wrapped up in a plot against King Henselt, who controls the region of Kaedwen. After helping him escape to the city of Vergen, Geralt learns of Triss Merigold is being held by members of the Nilfgaard kingdom from sorceress Philippa Eilhart. Eventually Geralt breaks a spell unleashed onto the battlefield and helps repel attacks on Vergen by King Henselts forces alongside the Scoia'tael and the rebel leader Saskia the Dragonslayer.
Geralt later discovers Saskia is a dragon taking human form whose mind is being controlled by Philippa Eilhart. Once this is discovered, Philippa teleports Saskia and herself to the city of Loc Muinne, where Triss is being held. Geralt and Iorveth follow toward Loc Muinne, where a summit of royal leaders is taking place and is central to the sorcerers motivation for her control of Saskia.