SPOILER WARNING: This article contains major spoilers for "The Wrath of Rama Khan," the midseason finale of Supergirl.
Lex Luthor lives! In "The Wrath of Rama Khan," the Supergirl midseason finale, the major Superman villain was alive and well. However, since he is being kept at the Monitor's base of operations, it looks as though Mar Novu has big plans for him in "Crisis on Infinite Earths."
After the Monitor recruited Martian Manhunter, he returned to his headquarters, which looks to be a platform floating through empty space. There, he found Lex playing chess against himself. "Finally, you've returned," Lex said, putting his hand on his hip. "I don't know if anybody's told you this, but the feng shui of this place is a bit stale."
The Monitor ignored that. "I brought you back because the universe will need a mind like yours," the Monitor explained, holding the Book of Eternity under his arm.
"Someone who can checkmate anyone?" Lex posited.
"The time has come for you to fulfill your destiny, Lex Luthor," the Monitor announced. "You can now become the hero that you have longed to be."
"I've always been the hero," Lex retorted. The Monitor merely looked down at him with a grim expression, so Lex added, "Happy to help. But first, we have to discuss my sister."
Lex has an axe to grind with his sister Lena. After all, in the Season 4 finale, she shot him in the chest and killed him. After she left her brother to rot, the Monitor stepped in. It appears he resurrected Lex, who has a role to play in next week's "Crisis on Infinite Earths" crossover event -- and he's not the only one.
According to the episode description for "Crisis on Infinite Earths, Part One," J'onn J'onzz and Alex Danvers will go to Lena for help in an effort to save the people of their Earth: "With their worlds in imminent danger, the superheroes suit up for battle while J'onn (David Harewood) and Alex (Chyler Leigh) recruit Lena (Katie McGrath) to help them find a way to save the people of Earth-38."
Given the events of Season 5 so far, Lena may be reluctant to help. As he lay dying, Lex revealed to her that Kara had been Supergirl all along. Lena was gutted, believing that Kara had lied to her for their entire friendship. In response, she launched Project Non Nocere, her plan "to rid humanity of its instincts to hurt each other." Since Supergirl and her friends put a stop to Project Non Nocere, Lena probably won't be charitably disposed towards Alex, J'onn or anyone involved with Kara. However, the events of "Crisis" may force her to work with them nonetheless.
Lex Luthor will return in "Crisis on Infinite Earths," which begins Sunday, Dec. 8 at 8 p.m. ET/PT on Supergirl, then continues in Batwoman on Monday, Dec. 9 at 8 p.m. ET/PT and in The Flash on Tuesday, Dec. 10 at 8 p.m. ET/PT. After the winter hiatus, the crossover will conclude on Tuesday, Jan. 14 in Arrow at 8 p.m. ET/PT and in DC's Legends of Tomorrow at 9 p.m. ET/PT.