You Never Can Taillow (Japanese: スバメがいっぱい 危険がいっぱい！トウカの森でゲットだぜ！！A Lot of Subame! A Lot of Danger! Capture in Touka Woods!!) is the fourth episode of the Advanced Generation series and the 278th episode of the Pokémon anime. It was first broadcast in Japan on December 12, 2002 and in the United States on November 22, 2003.
Ash, Pikachu, May and Max are walking in the Petalburg Woods. May complains that she is hungry while Max complains that he hasn't seen one new Pokémon yet. The two start to bicker about what to do next, pulling Ash in two directions until he and Pikachu yell for them to stop. Ash decides they'll take a quick lunch break and then decide which way to go, but there's one problem: none of them have brought lunch with them; even Pikachu's food canister is empty. Ash apologizes for messing up, then wishes Brock were there, telling May and Max about him, especially how good a cook he is. Max pulls out his "emergency stash," a chocolate cookie. They agree to share the small treat, when suddenly a Taillow swoops in and snatches it. They chase the Taillow, with May incensed over the food theft and Max excited that he finally found a Pokémon. The Taillow soon eats the chocolate, and Max asks if he liked it. Pikachu discovers that they are in a grove of fruit trees. Ash tells Pikachu to shock down some fruit; however, numerous Taillow appear and snatch it up before it hits the ground. Then more Taillow appear and surround the group, looking angry. Ash wonders if it's because they're in the Taillow's territory. Ash orders Pikachu to Thunderbolt them; the Taillow are knocked down, but recover quickly. A second Thunderbolt is also shaken off. Jessie, James and Meowth watching from the bushes, are impressed with the Taillow's resilience. They speculate that catching Pikachu would be easy if the fierce Taillow were on their side. Meanwhile, Pikachu continues to shock the Taillow, hitting one that May spots as the leader. Max notes that the chocolate mustache on its beak marks it as the cookie-thief. The Taillow shrugs off Pikachu's attack and leads the others in a mass attack on our heroes. They prepare to be hit hard when a figure appears, throwing a Poké Ball and commanding Forretress to use Explosion. It is Brock to the rescue. Introductions are made, and then Brock offers the others rice balls only to discover they have been stolen from his backpack. He offers to cook up some stew instead. A little way off, Team Rocket make use of the Taillow, bribing them with the stolen rice balls to capture Pikachu. Meanwhile, the chocolate-beaked Taillow has (seemingly on its own) shown up to challenge Pikachu, and Ash enthusiastically agrees. They battle over the stream but the Taillow, despite taking several Thunderbolts and a massive Thunder attack, refuses to back down. Brock tells Ash to stop the fight before he hurts it any more - he'll have to catch it. Ash throws a Poké Ball and captures Taillow. Ash calls his new Taillow out, Brock spritzes it with medicine and Ash wipes the chocolate off its beak with Misty's handkerchief while Ash, Pikachu and Taillow do a victory pose. Team Rocket then makes their appearance, ordering the Taillow to attack, but Brock's cooking alarm goes off, announcing the stew is ready. Brock offers to share with the hungry Taillow flock, who lose interest in fighting. Team Rocket mourns the failure of their plan, but go to attack anyway, figuring Pikachu will be weak with hunger. However, they get blasted off, as Ash informs them that Pikachu ate Brock's Pokémon food already. Taillow says goodbye to its flock, as our heroes continue their journey, now joined by Brock and Taillow.
After catching it, Ash let out his new Taillow and cleaned off its chocolate mustache with the same napkin Misty gave him when they said goodbye. Coincidentally, this episode also features Brock's return.
The title is a reference to the phrase "you never can tell."
This may be one of the only times that a Poké Ball does not shake or wobble when a Trainer catches a Pokémon.
Ash, May, Brock, and Team Rocket break the fourth wall in this episode when they fight for a larger portion of the split screen.