Here’s some background on the mysterious Dark Ones players encounter throughout the Metro 2033 video game series. The original game was based on the bestselling Metro 2033 novel by Dmitry Glukhovsky, which is set years after a nuclear attack on Russia. The survivors went underground and eke out an existence in the dark tunnels of the sprawling metro system. Adding to the stress are rival factions and assorted mutated creatures running around.

After the book became a success it was adapted into a video game in 2010 and the franchise has proven surprisingly robust. The book spawned two sequels - Metro 2034 and Metro 2035 - and various comic spinoffs, while the game series received follow-ups Metro: Last Light and Metro: Exodus. Given the franchise’s strong foundation of action, horror and politics it seems like a natural for a big-screen adaptation, but an attempt by MGM to make a movie version set in Washington D.C. didn’t work out.

Despite this failed attempt, author Dmitry Glukhovsky announced in 2019 that a movie version of Metro 2033 was coming in 2022. Whether or not it can recapture the unique blend of elements that made the original novel and game work remains to be seen. The Metro franchise has also built up a lot of lore, especially in regards to the Dark Ones. These mysterious beings serve a similar function in both the novel and the game. They are defined by their dark skin, long limbs, and they have powerful psychic powers that can induce hallucinations.

The exact origins of the Dark Ones is unknown throughout the Metro 2033 franchise, with theories ranging from them being humans who somehow adapted to the radiation on the surface or they’re the result of experiments from before the nuclear attack. Metro 2033 presents them as enemies, with the ultimate goal being to destroy their nest on the surface. It’s later revealed their intentions are benign, with the combination of the Dark Ones unknowable nature and humanity’s fear of them and their abilities leading them to assume they’re hostile. Artyom learns this a little too late, and in both the novel and game, the nest is destroyed.

Artyom is haunted by this in Metro: Last Light, so when he finds a baby Dark One, he decides to protect it from the multiple factions who either want to kill it or control it. The happy ending of Metro: Last Light reveals a group of surviving Dark Ones coming out of hiding to turn the tide of the final battle, before departing - alongside the baby Dark One - for the surface. The creatures make a couple of cameos in Metro: Exodus, but they’re not the main focus of the story as in previous titles. The Dark Ones are basically an allegory for xenophobia in the world of Metro 2033, and while their intentions may be somewhat mysterious, its clear they wish to co-exist with humanity.

Next: Metro Exodus Survival Guide: How To Master The Day & Night Cycle