Blondas Have More Fun! is the seventh episode of Season 5.
Timmy and Cosmo are enjoying some of Timmy’s more “extreme” wishes when Jorgen poofs in, annoyed at Wanda for not taking better care of her two charges. Wanda’s incensed – how is this her fault? Jorgen tells her she needs to take control and be more like her identical-but-somehow-hotter sister, Blonda. Timmy didn’t know Wanda had a sister, and is surprised to learn she stars on Jorgen’s favorite soap opera, “All My Biceps.” Wanda explains that while she took the responsible route and became a fairy godparent, Blonda followed a more selfish path that took her to Fairywood. Cosmo can’t recall why they haven’t visited Blonda – until the three poof to Fairywood and Blonda and Wanda immediately get into an argument.
Timmy is all out for extreme wishes. But when the attempted stunt with a half pipe to jump over a shark pool with rocket rollerskates goes wrong, Wanda hopes that she doesn't get blamed. The scene then cuts to Jorgen, blaming Wanda for failing to put her foot down. He compares her to her richer and somewhat hotter sister named Blonda, who stars on his favourite soap opera All My Biceps. As the show is about to start, he poofs back to Fairy World.
Meanwhile, in Fairywood, Blonda is in the middle of a live action filming of her show, where she has to kiss Dr. Poof Everwish. As the episode ends on a cliffhanger, Blonda then gets envious that everyone in Fairywood has a Zappy award except for her. Cutting to an interview with Fairy Hart, Blonda expresses her wish to have a simple life with an idiot and a godchild like Wanda. Watching this on a TV, Wanda poofs her family to Fairywood to confront her sister. Timmy asks Cosmo why they never met Blonda. As Cosmo tries coming up with an answer, Wanda and Blonda come to blows against each other; he then remembers that they hate each other. As Timmy and Cosmo poof back to Earth for bear wrestling, Wanda and Blonda decide to switch lives for the day after arguing about each other over who has it easier (Wanda initially thought that they should try samurai swords to the death). Wanda has a fun time in Blonda's place, but Blonda has a heck of a time trying to deal with Cosmo and Timmy's antics, Jorgan's bossiness, and the insanity of Dimmsdale; she even had to poof back to Fairy World to get Timmy and Cosmo's name.
Unfortunately, Wanda becomes harassed by the evil paparazzi taking pictures of her being buck naked in a hot tub. Chased out of Blonda's dressing room, Wanda finds herself on the set. As she is instructed to kiss Dr. Poof Everwish during the live filming, she refuses, thus threatening the cancellation of All My Biceps. Jorgen decides there are only two things to do: hit Binky, and blame Wanda again. Jorgen poofs to Earth, where Blonda is viewing Timmy ready to be fired out of a cannon right into a Cosmo net in Australia. Jorgen blames Wanda, not knowing her to be Blonda, for her sister's behavior. This is enough for Blonda to snap, as she threatens to fire Timmy at Jorgen. She promises to save the show but first makes Jorgen swear not to blame Wanda anymore (Jorgen is confused as to why they are talking in third-person) and Timmy not to do anymore extreme stunts. Blonda then realizes neither of their lives are better; meanwhile, Timmy is fired from the cannon but misses the Cosmo net, who is distracted by the sight of a baby kangaroo in its mother's pouch. She poofs back to Fairywood, where she saves the show and improvises by saying that Wanda is her evil twin and they switch back to normal. As the paparazzi start to pester them, the sisters decide to settle this with samurai swords to the death.
Blonda and Wanda's relationship is much better, following these events, but this doesn't last long. At the Zappy Awards, Wanda gets awarded a Zappy, much to the jealousy of Blonda. Wanda and Blonda then do a samurai battle to the death match. Timmy and Cosmo go back to extreme stunts but once again, Timmy misses.