Season two of "Supergirl" has canonized a major part of the Superman mythos as part of the CW's Arrowverse: the Luthors. While Lex Luthor himself isn't a part of "Supergirl," his sister and mother sure are. Lillian (Brenda Strong) and Lena (Katie McGrath) have made their presence felt on the show so far, albeit in opposite ways. Kara (Melissa Benoist) has struck up an alliance of sorts with Lena, while Lillian has so far proven herself to be a master manipulator and evil schemer.

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The pair of Luthors will take the lead in the next episode of the series, an installment appropriately titled "Luthors." The CW aired a promo for the episode, and it confirmed that an episode titled "Luthors" has to include a shout out to Lex. At 12 seconds into the promo below, you catch a glimpse of what appears to be Lex Luthor's iconic green and purple warsuit. The CW shows have not shied away from diving deep into their comic book origins, so the warsuit's inclusion feels right in line with the rest of "Supergirl."

"Luthors" also doubles as the season's Valentine's Day episode. The B-plot will follow Supergirl's sister Alex (Chyler Leigh) as she navigates her first Valentine's Day with a girlfriend (Floriana Lima). Unfortunately for Alex, Maggie Sawyer isn't really a fan of Valentine's Day -- thus leading to their first big couple fight. You can find out more about the episode in the synopsis below.

“Luthors” — (8:00-9:00 p.m. ET) (TV-PG, V) (HDTV)

LENA IS ARRESTED – After Metallo (guest star Frederick Schmidt) breaks out of prison and frees Lillian Luthor (guest star Brenda Strong), the police blame Lena (guest star Katie McGrath) for his escape and arrest her. Despite overwhelming evidence, Kara (Melissa Benoist) refuses to believe her friend is guilty and fights to clear Lena’s name. Flashbacks reveal how Lena came to be a Luthor. Meanwhile, Alex (Chyler Leigh) and Maggie (Floriana Lima) celebrate their first Valentine’s Day together. Tawnia McKiernan directed the episode written by Robert Rovner and Cindy Lichtman. (#212). Original airdate 2/13/17.

Starring Melissa Benoist as the Girl of Steel, “Supergirl” airs Mondays at 8 pm ET/PT on The CW. The series also stars David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers and Jeremy Jordan as Winn Schott and features appearances by Calista Flockhart’s Cat Grant as well as Tyler Hoechlin’s Superman.