Warning: SPOILERS for The Witcher season 1

The Witcher season 1 finale teased a well-known character from Geralt of Rivia's past. Geralt's world, known as The Continent, is most widely-known via a series of popular video games. Developed by CD Projekt Red, the first installment of the same name was released in 2007. It was eventually followed up by 2011's The Witcher 2: Assassins of Kings and then The Witcher 3: Wild Hunt in 2015. The games, however, are based on the series of stories written by Polish author Andrzej Sapkowski. The season 1 finale of The Witcher teased an important character from the game and book series.

Netflix's adaptation takes the bulk of its inspiration from the books, while also nodding at the video games. The Witcher stars Henry Cavill as Geralt, the titular monster hunter. Witchers like Geralt are mutated to be gifted extraordinary abilities and trained from a young age; as a result, Geralt is a force to be reckoned with. He lives a solitary life, wandering between villages as a monster-slayer for hire. Equally, the series also stars Anya Chalotra as Yennefer of Vengerberg, a wildly mistreated yet powerful sorceress in training, and Freya Allan as Ciri, a young Princess who finds herself braving the wilds of The Continent when her Kingdom is overthrown. Ever the fantasy drama, The Witcher follows the trials and tribulations of all three characters at different points in time as fate conspires to ultimately bring them together.

Related: Netflix's The Witcher Season 1 Ending Explained: What's Next For Geralt

The Witcher season 1 concluded with Geralt and Ciri finally crossing paths. Destined to be Ciri's protector, as per an ancient tradition known as The Law of Surprise, Geralt finally embraces both the refugee Princess and his fate. Before that long-awaited moment, however, Geralt finds himself wounded by a horde of undead creatures. Delirious and drifting between the past and the present, The Witcher teases another important character from the source material. Reliving the childhood trauma of being seemingly abandoned by his mother, Geralt recollects a voice saying, "Geralt, I've been waiting for you." In his delirium, the memory provokes Geralt to call out the name Vesemir.

Who Vesemir Is In The Witcher Series

Henry Cavill as Geralt in The Witcher

Long-time Witcher fans will no doubt recognize the name Vesemir; as the oldest and most experienced Witcher, Vesemir serves as the fencing instructor at Kaer Morhen, which houses the Witcher School of the Wolf. Training under him, Geralt (and many other Witchers-in-training) came to view Vesemir as a father figure. When Kaer Morhen is besieged, Vesemir is the only Witcher present to survive. As such, he becomes the de facto head of the guild. Due to only being a fencing instructor, however, he lacked the knowledge the successfully mutate new recruits into full-fledged Witchers, leaving their kind scarce.

Based on comments from Geralt throughout The Witcher season 1, such a sacking of his home and culling of his kind has already taken place. And though many would have missed it, the actor voicing that line is confirmed as Theo James from the big screen Divergent franchise.Given how faithfully the Netflix show is adapting the source material, it's likely Vesemir survived as he did in both the novels and the video games, even if Geralt isn't yet aware. Therefore, it's probably a safe bet that he will factor heavily into The Witcher season 2 — appearing in both present-day and further flashbacks to Geralt childhood training. The casting of James, however, will likely surprise fans. After all, Vesemir is estimated to be anywhere from 300-years-old to around 1000. As such, James doesn't quite match up to expectations as a father figure to Geralt, especially since James and Cavill are around the same age.

Fortunately, James is credited as Young Vesemir, meaning that he will likely play the role in flashbacks. Meanwhile, a more suitably aged and grizzled actor will take on the role in the present day. Then again, however, even that poses more than a few questions. Given that Witcher's tend to age much slower than average humans, it's hard to believe that Vesemir continued to age dramatically while Geralt remained relatively the same after a certain point. Whatever the case ends up being, however, the arrival of Vesemir will no doubt still excite fans. And further details are sure to emerge between now and The Witcher season 2's 2021 release.

More: What To Expect From The Witcher Season 2