One possible plot development could be that Leia uses her wits to try and outsmart Vader during her captivity. She might attempt to manipulate the situation to her advantage, perhaps by feigning cooperation while secretly planning an escape. Another development could be that Luke and the Rebel Alliance launch a rescue mission. They would face numerous challenges, like penetrating Vader's stronghold and evading his forces. And Vader himself might be conflicted about his actions, given his relationship with Luke and the knowledge that Leia is his daughter, which could lead to some internal struggle within him.
Leia would most likely be defiant. She has always been a strong and feisty character. She would probably resist Vader's every move and not be easily intimidated by his presence.
In the 'Lockhart Kidnaps Harry Fanfiction', it could be that Lockhart is being controlled by a dark force without his knowledge. This dark force wants Harry for some evil purpose, like using his connection to Voldemort to resurrect the Dark Lord. Lockhart, being the vain and easily manipulated character he is, is just a tool in this scheme. He might initially think he's in control, but as the story progresses, he realizes he's in way over his head.
One possible plot development could be Sherlock using his brilliant deductive skills to outwit Moriarty even while being kidnapped. He might leave behind subtle clues for Watson to find him. For example, he could use Morse code by tapping on the walls if his hands are tied. Another development could be Moriarty trying to break Sherlock's spirit by taunting him with past failures or the safety of his loved ones. Maybe Moriarty has a grand scheme that involves Sherlock in some way, like using him as a hostage to gain access to certain confidential information from the British government.
Perhaps in the fanfiction, Esmeralda discovers a secret passage in the place where she's held captive by Frollo. She could use this to escape, but then has to evade Frollo's guards in the maze - like corridors. Also, there could be a plot where Frollo has some sort of internal struggle. Maybe a part of him starts to feel guilty about the kidnapping and debates whether to let her go.
Well, in this type of fanfiction, there are numerous possible plot developments. For example, Mabel might discover some hidden power within herself while being kidnapped by Bill. This power could be the key to her escape or to ultimately defeating Bill. Or, Bill could be using Mabel to access a different dimension or unlock some ancient mystery in Gravity Falls. And the Pines family, along with their allies, would then have to race against time to save Mabel and prevent whatever Bill's evil plan is. There could also be a lot of psychological warfare between Bill and Mabel, with Bill trying to break her spirit and Mabel remaining strong and defiant.
Well, in a fanfiction where Luke is captured by Vader, there might be a plot where Vader tries to make Luke his apprentice in a more psychological way. He could isolate Luke and feed him false information about the Jedi and the Rebellion. Luke, on the other hand, might resist by connecting with the Force in new and unexpected ways. Maybe he manages to communicate with other Jedi spirits who guide him through the tough situation. And, there could be a sub - plot where Luke's friends are trying to rescue him, leading to an exciting showdown between the Rebels and Vader's forces.
One possible plot development could be that Aang and the gang set out on a rescue mission. They might face various obstacles along the way, like dealing with Jet's group's hiding places. Another could be that Katara, while kidnapped, tries to reason with Jet, appealing to his better nature if he still has any left. Maybe she manages to convince some of his followers to turn against him.
Perhaps the kidnapping is part of a larger plot by an enemy of both the Winter Soldier and Darcy's friends. The Winter Soldier might be used as a tool, and Darcy could end up being the key to breaking his brainwashing. She could start to form an unexpected connection with him during her captivity, leading to a change in both of their fates.
In a non - adult 'Sasuke kidnaps Naruto' fanfiction, a possible plot development could be that Sasuke kidnaps Naruto in order to protect him from a greater threat that he doesn't think Naruto is aware of. Maybe there's a new enemy in the Naruto - verse that Sasuke believes only he can handle, and he thinks Naruto will be safer away from the action at first.
One idea could be a story where Darth Vader discovers Leia's true identity earlier and struggles with his loyalty to the Empire and his newfound knowledge of his daughter. He could secretly protect her from the Emperor's wrath.