Wow, Lena Luthor and Kara Danvers have amazing chemistry. And on the other hand, Kara and Mon-El don’t really except as a goofy friend/superhero apprentice and master deal even though they excel at lobbing insults at each other. Luckily, writers Robert L. Rovner and Cindy Lichtman in “Luthors” in which the main conflict is almost every character writing off Lena as just another villain even though she hates her mother Lillian. In the fighting front, Lillian sends a dying of synthetic kryptonite poisoning Metallo and Cyborg Superman to rescue her so her campaign against extraterrestials can continue. Plus there are plenty of flashbacks featuring a young Lex Luthor and Lionel Luthor to show Lena’s twisted life, and why she leans on Kara so much.

Rovner, Lichtman, and director Tawnia McKiernan strike gold in “Luthors” by centering much of the plot, relationship drama, and suspense around the characters of Lillian and Lena Luthor, who are played with maternal rancor and a potent mix of strength and vulnerability by Brenda Strong and Katie McGrath respectively. McGrath has a talent for body language visibly shirking away from Metallo when he busts her out of prison where the guards constantly insult and mistreat her. And when Supergirl comes to stop Metallo and Lillian, she instantly runs for her. This open vulnerability that she shares with Kara, who brings her donuts in a super cute scene, is immediately replaced by combativeness as it is revealed that she is the daughter of Lionel Luthor and his mistress, which wasn’t great for Lillian and Lena’s relationship growing up. But the manipulation is counterbalanced by the paradigm challenging friendship (With heavy romantic subtext.) between Kara and Lena, who feels safe and happy around Kara, and isn’t afraid to hug her when she is mostly distant around her mother and the people in the courtroom early on.

Brenda Strong has been sorely missed the past few episodes, and her ability to turn from wannabe nice mom to goal oriented anti-alien fanatic is on full display in “Luthors”. Lillian plays Lena like a musical instrument as McKiernan instantly cuts to her daugher’s teary face when she talks about finally having a good mother/daughter relationship now that Lex and Lionel are out of the picture. But she really just needs Lena’s Luthor DNA to unlock a special vault filled with all kinds of goodies like Lex’s classic battlesuit, some sonic bombs, and more Easter Eggs that will likely pop up in episodes to come as Cadmus continues their war against Supergirl and her alien friends. And even when Lena puts two and two together, Lillian continues to try to soothe and comfort her like mother while leaving Metallo behind to burn out while she’s off to survive another day.

Metallo is decently well-used this episode as pure, if flawed muscle as his kryptonite blaster gives Supergirl serious problems and leads to a well-staged close quarters between him and J’onn, who channels his sadness over Miss Martian leaving into a fun last minute save. His core going nuclear is a boring action movie trope, but the fact that he has kryptonite after J’onn gave Superman the rest of his supply is a clever hook for most of “Luthors”. It’s also good to have a villain who can go toe to toe with Supergirl because you can’t win all the fights even if it looks like Metallo won’t be fighting any battles after this one. Metallo is just a plot device in “Luthors”, but works well as a distraction from Kara Danvers’ attempts to vindicate Lena as innocent because of their friendship.

And finally, we make it to our favorite part of each Supergirl review: where I continue to chronicle why the Kara/Mon-El relationship doesn’t work out on a romantic level. First, Robert L. Rovner and Cindy Lichtman have Mon-El talk about his failed date with Eve Teschmacher instead of reveling in all its awkward, disgusting glory with Chris Wood mooning all over Kara. This leads to some awkward dialogue throughout “Luthors” about Mon-El and Kara caring about each other dating other people, Kara choosing being Supergirl over having a boyfriend, and there’s no real bond between them or even story elements that show why Kara’s feelings have changed towards him. It’s like they’re looking for a reason to keep Mon-El, who does have a little bit of goofy charm thanks to Chris Wood, around, and the spinner landed on romance, not friend or hero-in-training. Luckily, their smooch is interrupted by a classic supervillain

“Luthors” puts some meat on the bones of the greatest villain in Supergirl Season 2 and one of Supergirl’s most unexpected confidants, Lena Luthor. Their backstory complete with low lighting and chess imagery from Tawnia McKiernan taps into the supervillain iconography implicit within the Luthor name, and she even leaves Lena’s true allegiance ambiguous even though she hates Lillian and loves Kara. (Yeah, I used the L word, deal with it.) The other plotlines featuring Mon-El and James Olsen seem a little forced although it’s nice to Kara and James as friends after their fantastic chemistry in Supergirl Season 1, but a comic book deep cut cliffhanger promises that next week’s will be more on the experimental and comedic side.

Overall Rating: 8.0