There are many possibilities. One is that Naruto's capture could be part of a larger plan by the Akatsuki. They might be using him as bait to draw out other powerful ninja from the Hidden Leaf. Or perhaps they want to extract the Nine - Tails from him. This would put Naruto in a very dangerous situation. He would have to rely on his own strength and wits, as well as any hidden allies he might find within the Akatsuki's ranks to survive and eventually escape.
In this fanfic, Naruto might be tortured for information about the Hidden Leaf. The Akatsuki are known for their ruthless ways, so they could use various jutsu to make him talk.
Well, if Naruto gets captured by the Akatsuki in the fanfic, it could lead to some interesting character developments. His friends in the Hidden Leaf would surely try to rescue him. And Naruto himself might try to find a way to escape while also learning more about the Akatsuki's motives and secrets. Maybe he could even turn some of the Akatsuki members around with his talk - no - jutsu.
It's possible that some unexpected characters could come to Naruto's rescue. For example, an old enemy of the Akatsuki who has a change of heart. Or perhaps some of the Jinchuriki who Naruto has befriended in the past. They might feel indebted to Naruto for his kindness and decide to help him out of the Akatsuki's clutches. There could also be a mysterious and powerful hermit ninja who hears about Naruto's capture and decides to intervene for the greater good of the ninja world.
In a 'naruto gets captured' fanfiction, he might be tortured for information. His captors could be after the secrets of his Nine - Tails chakra. They may try to use him as a bargaining chip against Konoha.
Well, if Naruto is captured by Orochimaru in fanfiction, one possibility is that Orochimaru wants to use Naruto as a bargaining chip against Konoha. He may think that by having Naruto in his grasp, he can force the Hidden Leaf to meet his demands, like giving him access to certain forbidden jutsu or secret scrolls. Another aspect could be Orochimaru's curiosity about Naruto's ability to master new jutsu so quickly. He might want to study Naruto's mind and body to find out the secret behind his growth as a ninja.
In such a fanfic, Naruto might be subjected to various interrogations by Kumo. They could be interested in his Nine - Tails power. Maybe they would try to extract information about Konoha's secrets through him.
In a fanfic where Arya gets captured, she might be used as a bargaining chip. Her captors could try to exchange her for something valuable, like a strategic location or a large sum of gold. Maybe they want to use her to manipulate the Starks.
Well, in this fanfiction, perhaps Steven could be held captive by an old enemy. Maybe he'll have to use his wits to escape, like finding a weakness in the prison's security system.
Well, perhaps Gengar is captured by a powerful trainer. The trainer might use a special Poké Ball to catch it. Then, Gengar could try to escape from the ball by using its ghostly powers.
In this fanfiction, Luffy might be used as a bargaining chip by his captors. Maybe they'll try to exchange him for something valuable, like a powerful Devil Fruit or a large amount of treasure. His crew would then surely launch a rescue mission, facing many challenges along the way.
In this fanfiction, perhaps Serena is captured by an evil organization. They might be after her special powers or knowledge. Then, her friends would start a rescue mission.
Well, in such a fanfiction, Sora might be held in a dark and gloomy dungeon. Maybe some old enemies from the original story could be behind the capture, seeking revenge.