Meg and Markayla were abducted by a human trafficking ring.
The boy that they thought they were chatting with online turns out to be a team of online perverts.
After the two decide to meet the boy for a concert, they are tricked by a woman who claims to be the boy’s mother. When the team manages to track down the picture that the UnSubs used, Kate recognizes the ruse; it’s the same human trafficking ring from Season 10, Episode 1. Kate spent her off-time trying to dig deeper on the case, which is why Meg was taken.
Markayla manages to escape when the two are transported to a new location, but Meg remains in the clutches of the traffickers. Using the techniques that Kate taught her, Meg uses reverse psychology to the best of her advantage, but gets sold to a sex offender. The members of the BAU manage to infiltrate the site and one of the sellers and save Meg in the nick of time.