Warning: spoilers ahead for the penultimate episode of Legends of Tomorrow Season 3, called "Guest Starring John Noble."
The third season of Legends of Tomorrow spent 17 episodes more or less building to the release of Mallus into the physical world, and the terrifying twist finally happened in the final moments of "Guest Starring John Noble." The majority of the hour actually featured the Legends scoring some major wins, and it seemed at first that they might actually win. Given that this was the penultimate episode and the Legends' luck never seems to last, everything inevitably went wrong. Mallus was unleashed from Nora Darhk's body, and it's difficult to imagine how he can be stopped.
The Legends split up early in the episode when Nate and Wally went after Amaya, who had returned to her village to prevent it (and her family) from being massacred. The rest of the crew had to deal with the sudden arrival of Damien Darhk, who had decided that it was more important to save his daughter's life than continue working with Mallus and battling the Legends. Darhk seemed to be telling the truth, and his love for his daughter was sincere enough that even Sara was able to temporarily overcome her desire to kill him to accept his help.
The team-up with Darhk actually got off to a pretty humorous start as he first tried to earn their trust and then expressed bewilderment at the Legends' ridiculous plan for trying to get Nora, which involved tricking John Noble to read lines as Mallus while on the set of Lord of the Rings so that Ray could miniaturize himself, fly into Nora's ear, and play John Noble's voice inside of her head. Nora was convinced to go after the Waverider, where she was captured by the Legends. They came up with a plan that involved saving Amaya's village, bringing Mallus into a physical body so he could be killed, and saving Nora. Everything went wrong when Damien Darhk -- as supervillains are wont to do -- betrayed them.
Unfortunately, Darhk betrayed them AFTER getting his hands on the death totem, which greatly enhanced his powers. Darhk was able to free Grodd to annihilate Amaya's village while he tried to save Nora. As it turns out, however, Nora was already gone, consumed by Mallus. He was finally unleashed and manifested as what can really only be described as a giant demon monster. Mallus is unleashed, and everybody might be totally screwed.
You can catch the season finale of Legends of Tomorrow on Monday, April 9 at 8 p.m. ET on The CW. For what you can watch following the end of Season 3, check out our midseason TV premiere guide and our summer TV premiere schedule. If you're still in the mood for superhero action, we have a handy superhero TV premiere rundown. Legends just scored a renewal for Season 4, which means we'll see a whole lot more of a certain character.