Commissioner James Gordon plans a peaceful ‘Flower-In’ at Gotham City Park, only to learn that there are no flowers available anywhere. Meanwhile, the licentious Louie the Lilac devises a plot to take over the minds of Gotham City's flower children; using his hypnotic Lilac Spray he abducts Princess Primrose from the florally-challenged flower-in, causing the furious flower children to begin a demonstration outside City Hall. Louie’s scheme relies on the knowledge that Primrose is actually Thelma Jones, an old school friend of Barbara Gordon, which ensures that Batman and Robin get to hear of the kidnapping and while Batman and Robin talk to Barbara, Louie plants a card for Lila's Lilac Shop in the Batmobile. Having found the clue, the Dynamic Duo head for the flower shop, but Louis overpo