Nightmare of the Wolf will provide The Witcher’s most important backstory. A little over a month after The Witcher debuted on Netflix in December 2019, news of an anime movie was confirmed. A prequel of sorts, The Witcher: Nightmare of the Wolf is set to follow Vesemir, Geralt of Rivia’s mentor, in the early days of his journey as a witcher. Vesemir has already been confirmed to appear in season 2 of The Witcher, where he will be played by Killing Eve’s Kim Bodnia. While plot details are relatively scarce, the anime film could explore the siege of Kaer Morhen, a crucial event in witcher history that could add more depth to season 2 of the show.
The siege (or battle, as it is usually referred) of Kaer Morhen, the ancestral castle where witchers trained and underwent mutations, was an event that played out in The Witcher 3: Wild Hunt. In the video game, the pivotal battle was instigated by the Wild Hunt, a spectral group of teleporting horse riders whose arrival served as an omen for war. They were intent on finding and kidnapping Ciri because of her immensely powerful magic (which had not been activated) and hunted her for a while. When Ciri was brought to Kaer Morhen for refuge, Geralt, Vesemir, and the rest of the witchers made a plan of defense, knowing the Wild Hunt was not far from catching up to them.
However, despite their best efforts, the Wild Hunt overpowered the witchers and several of them died, including Vesemir. Of course, knowing that Vesemir will be in season 2 of The Witcher means that he won’t be killed in Nightmare of the Wolf. The film is also reportedly an origin story, which suggests that the battle of Kaer Morhen won’t necessarily play out at all. That said, assuming that the film is released ahead of season 2, Kaer Morhen and the Wild Hunt could be introduced, which could then connect with The Witcher's primary arc. Vesemir is one of the oldest witchers, after all, and it’s possible that he had his fair share of run-ins with the specters.
What’s more, Kaer Morhen was a resplendent place before the siege and years wore it down. It also served as Vesemir’s primary home for a lot of his life. In fact, he was one of the last known witchers to live in Kaer Morhen. The siege is one of the most notable moments in witcher history, so there’s a chance that Nightmare of the Wolf will, at the very least, lay the foundations for it. There’s no telling what the movie has in store, but considering Vesemir will be a focus, the possibility for the event to be included or alluded to is high.
To be clear, the siege of Kaer Morhen only occurred in The Witcher 3: Wild Hunt and was not a part of Andrzej Sapkowski’s Witcher novels and short stories. It’s also not an event that has been referenced at all in season 1 of The Witcher, which could mean that it hasn’t even happened yet. Regardless, the battle is an important part of witcher history and, with the series introducing Kaer Morhen in season 2 and Geralt bringing Ciri there to train, Nightmare of the Wolf could further explore the location before leading into the siege, thus providing another layer to The Witcher.