En route to Goldenrod City, our friends pass by a lake. Misty lets out all her Pokémon so they can swim, but Psyduck can't remember how to swim and has to be lifted out of the water. Ash releases Totodile too, it spots some Magikarp and uses its Water Gun to toss them into the air. Misty comments that Totodile is talented.
As everyone is having lunch, Totodile sees a female Azumarill sitting on the shore, singing. At once Totodile falls in love and runs over to dance in front of the Azumarill. She isn't impressed and blasts him with a Water Gun before walking away. Totodile follows her. At the table, the kids see a Golduck in the bushes. Misty wants to catch it but Brock says to wait, it seems to be looking for something. Shortly a girl with a Pidgey on her shoulder comes along, looking upset. Brock gives her a long-winded introduction of himself, and she tells him her name is Trixie. Brock flirts with her and Misty drags him away.
Ash asks Trixie what she's looking for, and she says she has lost her Azumarill. As if on cue, the Azumarill appears and hides behind Trixie's legs. Ash consults Dexter: Azumarill is the evolved form of Marill and can hear for great distances, even underwater. Now Totodile comes out of the bushes and blows kisses at Azumarill but she turns up her nose at him.
Later, they all gather at a circus tent. Trixie has always enjoyed the circus and taught her Pokémon to do tricks. Lately she's had trouble with Azumarill, who has been acting strangely since the Golduck joined the troupe
. Brock is helping set up for the show. Totodile helps too by filling a wading pool with water. He picks up Azumarill and puts her in the pool, only to be blasted with her Water Gun again. Ash doesn't understand why Totodile is acting this way, and Misty tells him that he'll understand when he's older and more mature.
The show starts. Trixie does a a magic act first, then Azumarill comes on and juggles coloured balls with her Water Gun. Totodile gets away from Ash and jumps up on the stage, showing off his own water tricks with fruit tossed to him by the audience. Annoyed, Azumarill walks away. Ash climbs up on the stage to try to catch Totodile and ends up having to catch the fruit when Totodile runs after Azumarill. Fortunately the audience think it's all part of the show. Brock decides to do something about the problem - he'll teach Totodile how to be successful in love!
Team Rocket has been watching the show, they plan to steal Azumarill and Pikachu so they can start their own travelling circus and get rich. Meowth isn't too happy with the idea, he doesn't want his tail to be Totodile's chew toy.
Ash apologises to Trixie for Totodile's behaviour. Misty wonders where Brock is, it turns out he's outside with Totodile. He gives Totodile a jar of his homemade Pokémon treats and suggests that Totodile give them to Azumarill. Totodile does so, but is rejected again.
Suddenly a net comes down, captures Azumarill and drags her away! Totodile chases after Azumarill as Brock watches from the bushes. Ash and Misty hear Brock's yell and come to investigate. Totodile chases the captive Azumarill and tries to grab the net but misses. Team Rocket appear in their balloon, with the net dangling below it. Ash orders Pikachu to attack but Meowth uses a device to catch Pikachu in an electric-proof cage! A Smokescreen attack from Weezing allows TR to escape, but Totodile runs after the departing balloon. Azumarill struggles and loses the ribbon that was tied to her tail. Totodile catches it, and as TR floats away, Totodile jumps into the lake and resumes the chase by water, ignoring Ash and Brock's yells to come back.
The three of them tell Trixie that Azumarill and Pikachu are gone. Misty isn't about to give up and suggests they search the forest on the other side of the lake.
Team Rocket is hiding out in a log cabin. J&J try to persuade Azumarill to do tricks for them but she refuses. They even make her a meal fit for a king but she still won't do as they ask. Eventually they resort to using force, but they are stopped by a Water Gun attack from Totodile, who has found them. Meowth muzzles Totodile and ties him up.
Meanwhile, Ash and company are searching through the forest with Trixie and Golduck. It'll be dark soon, so they decide to continue in the morning. Ash is upset but there's nothing much he can do.
Later that night, TR is sleeping in their cabin. The three Pokémon are all in cages now. Azumarill looks out the window at the moon and starts to cry, but Totodile gives her ribbon back and cheers her up by dancing.
In the morning, Team Rocket prepares to leave. Instead of their circus plan they'll take the Pokémon to the boss for a reward. As they lift off in the balloon, they are spotted by Trixie's Pidgey, which pokes a hole in the balloon and they crash. The cages fall out, Ash gets Pikachu and Totodile back but TR is holding onto Azumarill. Trixie sends Golduck to attack, and its powerful Water Gun makes short work of Weezing and Arbok. Bulbasaur's Razor Leaf easily takes care of the cages, and Totodile uses its Water Gun to knock TR over so that Bulbasaur can grab Azumarill's cage with Vine Whip. Then Pikachu's Thunderbolt sends them blasting off again.
Bulbasaur frees Azumarill and she's very happy. At Brock's urging, Totodile runs to her, but to everyone's surprise Azumarill runs right past Totodile and hugs the Golduck! Now Trixie understands why Azumarill has been acting strangely, she was lovesick over the Golduck. Brock tells the disappointed Totodile that although you can't win every time, love is worth fighting for.
The three friends depart. Brock flirts with Trixie one last time and has to be dragged away. Ash calls Totodile, who is sitting on the shore of the lake watching a female Quagsire. He runs to the Quagsire and dances for her, but gets rejected. Misty sighs, all they need is a Pokémon that behaves just like Brock! Ash is forced to chase Totodile with his Lure Ball, as he tries to get him to return.