Lex Luthor digs up a hidden tomb under Stonehenge and discovers the Book of Eternity, which lets a person read the future. When Batgirl can't get out of visiting her grandma they instead turn to Catwoman to mastermind a break-in to Lex's corporate headquarters to keep the book out of his hands.
Tropes:
- Air-Vent Passageway: Karen shrinks down and flies through the air vents to get to the security room, but she gets waylaid by a spiderweb... and the spider.
- All for Nothing: The Superhero Girls team up with Catwoman to steal the Book of Eternity away from Lex Luthor...only for it turn out she was working with Lex to lead them into a trap the whole time.
- Arson, Murder, and Jaywalking: At the end, Babs is upset over missing the fact Lex Luthor is a villain; saving the world with the other Super Hero Girls; and the appetizers.
- "Blackmail" Is Such an Ugly Word: The Superhero Girls blackmail Catwoman to help them run a heist under the threat of sending her to prison for her attempted theft of a painting. Wonder Woman denies that it's blackmail, though Catwoman points out that how she describes it instead is the literal dictionary definition.
- The Bus Came Back: After only having his company regularly name-dropped throughout the episodes and shorts, this is Lex's first appearance in person since "#SweetJustice", and it makes the most of it.
- Camera Spoofing: Karen's job is supposed to be sneaking into the security room and freezing the feed to the elevator camera. Unfortunately, she doesn't get a chance to do so.
- The Caper: Part one is about an elaborate plan to steal the things they need to get into Lex Luthor's vault...and the girls' attempts going humorously awry because they're heroines, and not good at being sneaky.
- Chair Reveal: Punctuated — off the idea that he might be evil — with, "I prefer the term 'visionary'." Supergirl's immediate reaction is that "that chair spin definitely reads 'evil'."
- Colony Drop: Lex is going to let an asteroid hit the planet and destroy society so he can take over. His plan is to capture all the superheroes so there's nobody around to stop it.
- Didn't See That Coming: Despite having a magic book that tells the future, Lex didn't foresee Catwoman turning on him when she found out he was going to let the world be destroyed by a meteor so he could remake it in his image.
- Egopolis: Luthor plans to name the Earth after his reconstruction "LuthEarth" (although he admits the name might need some work).
- Even Evil Has Standards: Catwoman is horrified that Lex's plan involves the deaths of countless people and the destruction of the world, which is why she foils it.
- Evil Plan: Lex's plan from reading the Book of Eternity is to remove all the superheroes of Metropolis so that an extinction level meteor strike isn't prevented, leaving the survivors dependent on his resources as he rebuilds the world in his image.
- Gilligan Cut: Babs saying she's sure she can get out of visiting her grandma to plan the heist, then Smash Cut to her waving goodbye as she's driven away to visit grammy.
- Godzilla Threshold: The girls are loathe to steal, but Zatanna convinces them that the power granted by the Book of Eternity is dangerous enough to do it anyway.
- Good Scars, Evil Scars: Indeed. Rather, in the imagined version of the heist, Supergirl starts a fight at Lex's party with a waiter with an ominous, Ernst Stavro Blofeld-esque scar over one eye, creating a distraction. In the real thing, when she insults a scarred hulk of a man, he... immediately falls over himself apologizing thinking that he must have offended her somehow.
- Imagine Spot: When Catwoman lays out their plan it shows all the girls flawlessly carrying out their different roles. You expect this to be the real thing with her explaining their jobs as we see it for narrative convenience, but then it peels back and that was just the planning session. The heroines constantly mess up their roles because none of them are used to being sneaky, or beguiling, or underhanded, like the villains are.
- Internal Reveal: The girls discover that Lex Luthor is a supervillain.
- Laser-Guided Karma: Although Lex gets cleared of all charges, he does has all his stuff stolen by Catwoman in the end.
- Kick the Dog: Supergirl can't resist laughing at seeing her jerk cousin Superman weakened and imprisoned by Lex. He feebly returns the sentiment when she gets subjected to the same.
- Missing the Good Stuff: At the end, Babs is upset that she didn't just miss the heist, but also saving the world.
- Never My Fault: Even though it was Supergirl's suggestion to conscript Catwoman's help, she pins the idea on Bumblebee after she betrays them.
- No Man Should Have This Power: Zatanna argues to the other girls that no one should have the Book of Eternity because it grants total knowledge of the future and thus the ability to control it. Not even someone as good as they believe Lex Luthor to be.
- Noodle Incident: Lex already defeated and imprisoned all the Invinci-Bros and Superman before the Super Hero Girls got involved. They're all still prisoners after it's over, so a second Noodle is how they got free.
- Oh, No... Not Again!: Superman's reaction to Lex playing dance music to nonchalantly dodge and defeat the Superhero girls, implicitly because it's repeat of how he was defeated.
- Screw Destiny: Catwoman stole the page out of the book that says she'll let Lex complete his evil plan so she can stop him, because nobody tells her what to do, especially a book.
- Something We Forgot: The Girls forgot and left the Bros and Superman imprisoned, and Catwoman didn't bother to release them either.
- Villain with Good Publicity: There's no small amount of irony in the Girls discussing the morality of stealing from such a famous philanthropist as Lex Luthor. After his plans are thwarted a press conference is held where he manages to absolve himself of all wrongdoing while spinning the Superhero Girls as dangerous vigilantes trespassing on his property.
