Her partner at work could also be very helpful. They know her work ethic and how important her job is to her. They would make sure she doesn't lose hope during the recovery process. They could bring her case files (if allowed) so she can still feel involved in the investigations in some way. This would keep her mind active and give her a sense of purpose during her recovery.
Castle would be the most likely. He has always been by her side, and his love for her would drive him to do everything he can to help her recover. He could use his resources, like his wealth and connections, to get her the best medical treatment. And he would also be there emotionally, constantly cheering her up and giving her the motivation to get better.
One possible plot twist could be that Beckett's injury is not as straightforward as it seems. Maybe it was caused by a mole within the department who wanted to stop her from uncovering a big case. Another could be that the injury leads to her developing a new skill or perspective while recovering, like learning to rely more on her other senses. For example, if she has a head injury that affects her vision temporarily, she might become better at listening for clues.
Beckett is the central figure here as the story revolves around her being hurt in the line of duty. Castle, her partner and love interest, would play a significant role. Additionally, the captain of the precinct might be a main character as he would be involved in the decisions regarding Beckett's situation, such as her leave of absence and the investigation into her injury.
Well, it could be about her colleagues rallying around her to support her during her recovery. Maybe Castle is by her side the whole time, trying to cheer her up and also using the situation as inspiration for his next book.
Bobby could also be a key figure. He's like a father figure to the boys and has a wealth of knowledge. He might know of some old remedies or be able to point them in the right direction to find a way to heal Dean. Charlie could also pitch in. She's smart and resourceful and could use her hacking skills to find information related to Dean's injury.
A coworker who has a crush on Beckett might be a main character. They could be the one who stays by Beckett's side the most during his recovery, and this could lead to a romantic sub - plot.
Katara would be a likely character to help Toph recover. Katara is a waterbender and has healing abilities. She would use her skills to tend to Toph's injuries, whether they are physical wounds or internal damage from overusing her earthbending. Another one could be Aang. He's the Avatar and has a deep connection with all the elements. He might use his spiritual knowledge to help Toph heal faster, maybe by finding a special place for her to rest and regain her strength.
Tails is very likely to help. He's Sonic's best friend and is super smart when it comes to technology. He could build a device to speed up Sonic's recovery or find a way to treat Sonic's injury. Amy is also a possibility. She's very caring and would do anything to make Sonic feel better. And Knuckles might help too. He's strong and could protect Sonic while he's recovering.
Perhaps the fanfic focuses on Beckett's struggle with the physical pain and mental stress of being injured on the job. It might show how he has to deal with insurance companies, doctors, and his own insecurities about whether he'll be able to return to work in the same capacity.
Perhaps a deranged fan of Beckett. Maybe Beckett is a well - known figure, like an actor or a writer, and a crazy fan who has an unhealthy obsession abducts them. The fan could be thinking that by doing this, they can get closer to Beckett in some warped way.
The other dragon riders could also be in the fanfic. Fishlegs could use his knowledge of dragons and other lore to figure out if there's a dragon - related way to heal Astrid. Snotlout might initially seem more concerned with his own status but would probably end up helping in his own way, perhaps by providing some muscle when needed for tasks related to Astrid's care.