Wherefore Art Thou, Pokémon? (Japanese: ニドランのこいものがたりNidoran's Love Story) is the 100th episode of the Pokémon anime. It first aired in Japan on June 10, 1999 and in the United States on April 22, 2000.
Our heroes are on their way to Trovita Island when they come across two Pokémon trainers who seemingly hate each other, even though their two Pokémon are in love. He has a male Nidoran and she has a female Nidoran and all that the two Pokémon want is to be together. It takes Misty, the true romantic, to see that perhaps it's the two trainers that are in love as well!
Ash and his friends arrive in Yambera, where they meet a young Trainer named Emily. She is looking for her female Nidoran, nicknamed Maria, who has an orange ribbon around her neck. When she asks if they have seen her, Ash looks up Nidoran up on his Pokédex and learns about their gender differences. She pleads with them to help her and they agree. As they search, Ash and Misty eventually bump into Ralph, another kid from the town who is looking for Tony, a male Nidoran wearing a blue and purple ribbon. When Emily and Tracey return, Ralph calls Emily a kidnapper. Both Ralph and Emily begin to argue over their two Pokémon.
Tracey's Marill returns and leads them to a flower garden, where they find both Nidoran cuddling into each other. Tracey and Misty immediately realize what is going on, but Ash is clueless. Both Pokémon act very romantically, but shortly after, they are taken away by their Trainers, who insult the other's Nidoran. Ash and his friends then go to a sandwich bar and talk to the owner, who tells them Ralph and Emily's story. They both knew each other since they were children and competed in many of the same contests and caught many of the same Pokémon. Their Nidoran fell in love with one another, but any possibility of them being together has been dashed due to Ralph and Emily's intense rivalry.
The group leaves the sandwich bar at sunset when they spot Tony running in front of them. They follow him to a building where Maria is, and they start communicating romantically. Just then, Emily appears at the window and pours water over Tony. Ralph eventually finds Tony soaking wet and takes him back to his house, which happens to be right next to Emily's. As Misty vows to do something about the situation, Team Rocket eavesdrops on the conversation and vows to capture the two Nidoran.
Later that night, Misty writes two letters, one for Emily and one for Ralph, and pretends they are from each other. Meanwhile, Jessie has Meowth convince Tony and Maria to come away with Team Rocket by tricking them into thinking that it is the only way to be together. However, Meowth fails because of Tony and Maria's strong loyalty to their Trainers.
Misty's plan is set in motion, resulting in Emily, Ralph, and their Nidoran coming into the park. There, they both get into a heated confrontation, accusing each other of sending the other a stupid gift and letter. It is revealed that Misty sent Ralph a toy plane and Emily a bouquet of flowers, which ended in disaster since Ralph throws up when flying in planes and Emily had an allergy to Misty's flowers. They are interrupted when Team Rocket shows up, cross-dressing as a newlywed bride and groom. They grab Tony and Maria before saying their motto and making their escape in their balloon. Misty scolds Emily and Ralph for fighting and arguing, saying that it was their fault their Pokémon were stolen. Ash and Tracey notice a trail of cans that fell from Team Rocket's balloon and follow it.
Team Rocket attempts to dress up Maria and Tony despite their squirming, only to have the gang find them. Tony and Maria make their escape, but Jessie commands Arbok to attack. Ralph and Emily command them to use Tackle, which knocks Arbok back. James joins in and calls out Victreebel. Maria uses Scratch on Victreebel while Tony gets knocked back by Arbok. Victreebel then traps Tony, but Maria rescues him. At that moment, both Ralph and Emily realize that their Pokémon are fighting for one another. Both Nidoran overwhelm Arbok and Victreebel with their teamwork, even improvising a Double Kick. As a result, Ralph and Emily coordinate their Pokémon without any further problems.
Team Rocket tries to escape and catch the Nidoran with a vacuum. However, Pikachu uses a branch to get to their balloon to avoid being blown in. He then uses Thunderbolt and destroys the vacuum. Misty calls out Staryu, who bursts the balloon, sending the trio blasting off. Afterwards, Misty has Ralph and Emily realize what they did wrong. Both of them finally listen and decide to do what is best for their Pokémon. As a result, Tony and Maria finally kiss, and in doing so, they evolve into Nidorina and Nidorino, much to their respective Trainers' delight.
Later on, as Ash and his friends bid farewell to Emily and Ralph, Team Rocket is seen being rung with Arbok and Victreebel on the church bells.
Also, they bore the colors of Raticate found in the mainland, which contradicts what Professor Ivy said in Poké Ball Peril. The Raticate at Ivy's lab were much darker, which, as Ivy explained, was a result of the tropical climate.
The use of a comma after the phrase "Wherefore Art Thou" in the title implies that the writers thought "wherefore" means "where" rather than "why".
The chef that appears in this episode looks remarkably similar to the one looking for a Psyduck in The Breeding Center Secret. His hat, hair, and mustache were similar, but the color of his hair and mustache were black instead of brown. He was also wearing an apron instead of a proper chef costume as in the former episode.
In the beginning of the episode, there is a dubbing error in which the narrator says Ash defeated Prima in the previous episode. In reality, Ash was actually defeated by Prima, and not the other way around.
In the scene with Maria and Tony, Ash and his friends chase Tony across town as he is visiting Maria. It is then revealed that this couldn't happen because they live next door to each other.
In the scene where Jessie and James go over their plan, Jessie's earring is colored blue instead of green.
In the Japanese version, Misty describes love as something very important to adults, and to her in particular as a woman. In response, Ash points out that Misty is still a child, causing her to get upset. In the dub, Misty describes love as "the most important thing in the world", and Ash says that it's "not more important than catching Pokémon." In the same scene, Ash gets upset over being called a "baby" in the dub, while in the Japanese version, he gets even more upset at the thought that Misty specifically thinks of him as a "kid".
At the end of the episode, in the Japanese version, when Ash asks about the kiss between the two Nidoran, Misty tells him, "A kid like you doesn't need to know!" In the dub, she says, "Guess we'll have to find out ourselves!"
At one point in the Japanese version, when Misty is talking about love, Ash gets confused and asks, "Koi...Koiking?" This is a pun on koi (恋), the Japanese word for love, and Magikarp's Japanese name. In the dub, Ash simply asks, "What do you mean?"