One possible plot could be that a deranged fan, feeling betrayed by the show's direction, kidnaps members of the Criminal Minds team. The kidnapper might demand that the show be brought back in its original format. Another plot could involve a criminal who uses the guise of a fanfiction scenario to target the team, perhaps because they believe the team has wronged them in some way. Maybe a group of obsessed fans accidentally kidnap the team while trying to get an autograph or exclusive access in a really over - the - top and illegal way.
It could be a disgruntled former crew member. Maybe they were fired from the show and in their anger, they read a lot of fanfiction for inspiration on how to get back at the team. So they plan and execute the kidnapping.
Well, perhaps a member of the unsub's (the kidnapper's) family or someone close to them has a change of heart. They might contact the BAU secretly and provide information about where Reid is being held. The team could then plan a stealthy operation to get Reid out. Also, Reid is very intelligent. He might be able to manipulate the kidnapper into making a mistake that the BAU can use to their advantage and rescue him.
One possible plotline could be that the unsub kidnaps JJ because she has been getting too close to uncovering his identity in a series of murders. The team then has to race against time to find her. They might start by retracing her last steps and interviewing people she was in contact with recently.
Another plot could involve a deranged fan who becomes obsessed with Spencer and decides to kidnap him but ends up taking another fan by mistake. This could lead to a situation where Spencer has to use his profiling skills to figure out who the kidnapper is and where they are holding the fan, all while dealing with his own guilt for the fan being in danger.
They'll likely interview people who had recent contact with Reid. The team will also analyze any communication from the kidnapper if there is any. Based on their profiling skills, they'll narrow down the suspects and search for the location where Reid is being held. Morgan might use his combat skills and Garcia will be crucial in providing technological support to find Reid.
It could be that Reid has unknowingly crossed paths with a criminal organization. They kidnap him to extract information about the FBI's investigations into their activities. Reid has to endure torture and interrogation, but he also tries to analyze his captors' behavior to find a way to escape.
It could be a former criminal that JJ put in prison and who has now been released and seeking revenge. Maybe it's someone from her past that she had a run - in with during her early days in the BAU.
One possible motive could be revenge. Maybe Reid has put away a relative or someone close to the kidnapper in the past. Another motive might be related to Reid's intelligence. The kidnapper could want to use his brainpower for some illegal or self - serving scheme, like cracking a code or coming up with a complex plan.
Hotch would immediately take charge and start organizing the team. He would be calm but determined to get JJ back. Morgan would be on the front line, ready to use his physical skills to track down the kidnapper. He'd be really angry and motivated to rescue JJ as she's like family to him.
One great Reid kidnapped fanfiction is 'The Abduction of Reid' on FanFiction.net. It has an interesting plot where Reid is kidnapped by an unsub with a personal vendetta. The author does a great job of building suspense and keeping the characters in - character.