The mayor has suddenly started a campaign to "Green Up Gotham" and more and more of the prominent citizens are getting behind it. But when Batman sees Penguin "killed" in a fight and Barbara Gordon sees her dad turn into a plant creature, the secret is revealed. But can Batman and Batgirl beat Poison Ivy before it's too late for Gotham?
This episode contains examples of the following tropes:
- Assimilation Plot: Poison Ivy's latest scheme.
- Bilingual Bonus: "Fleurs de Mal" means "Flowers of Evil" in French. In fact, the flowershop which serves as Ivy's hideout is named after the french poet Baudelaire, who published a book of poems by that name.
- Call-Back: Remembering that trying to reason with her former friend didn't work, Batgirl focuses entirely on taking Ivy down.
- Combat Tentacles: The plant copies can turn their arms into a mass of tentacles to attack.
- Designated Girl Fight: Batgirl fights her evil counterpart, finally defeating her with a lawnmower.
- Evil Knockoff: Poison Ivy makes these of Commissioner Gordon, the mayor, and even Batman and Batgirl.
- Explain, Explain... Oh, Crap!: Batman's reaction when he realizes that Commissioner Gordon was also replaced by a plant creature, and thus Barbara is in danger, while discussing what happened with the arrest with Alfred.Alfred: (after kicking the flowers that nearly attacked him into the fire) The Mayor is cultivating rather unusual plants, Sir.
Batman: He isn’t the only one. The police aren’t themselves, all the way up to… Gordon.
Alfred: Sir?
Batman: Barbara may be in trouble. - Felony Misdemeanor: Gordon arrests Batman partway through the episode. His crime? Killing a flower, illegal under the recently-passed "Vegetation Rights Act." Justified given who's pulling the strings.
- Lotus-Eater Machine: The flowers that have been springing up around Gotham make the originals dream of a world of green. Batgirl lampshades how peaceful it is.
- Minor Crime Reveals Major Plot: Batman investigating Penguin (actually one of Ivy’s clones) stealing silver iodide leads him to uncover Poison Ivy’s plot to replace the most influential people in Gotham (and Barbara) with plant clones.
- Out-of-Character Alert: Barbara realizes that the man offering her flowers is not her dad because he's too much into flowers for his taste. The fake Commissioner Gordon turns green after she tosses the flower into the pot she was making soup in, boiling it.
- Shout-Out:
- Possibly Commissioner Gordon turning green and saying, "Daddy's angry."
- Somehow the idea of people being replaced by creatures grown from plants as part of an Assimilation Plot seems veeery familiar...
- Also, the title, "Fleurs de Mal", is taken (with a fault) from Charles Baudelaire's volume of French poetry, named "Les Fleurs du Mal". Appropriately, the florist that delivers flowers to Comissioner Gordon is called "Beaudelaire's."
- Sympathy for the Devil: After foiling Ivy's plan, Barbara thanks her for the campaign to Green Up Gotham.
- Twitchy Eye: The right eye of the mayor replicant twitches as he announces the "Green Up Gotham" campaign.
- Well-Intentioned Extremist: Poison Ivy, as usual.
- Would Hit a Girl: Batman. But he knew she was a plant. If you look carefully before he punches her, you'll notice one of Ivy's pink flowers on her clothes, which is a hint.
