When Katniss Met Tris

Katniss and Peeta are kidnapped and there's only one person who would do this, President Snow. They are thrown out to a place far away from Panem, a place they have never been in to. A place that's surrounded by a fence and the city is divided into 5 factions. Katniss and Peeta encounter two people dressed in black with guns and tattoos in their bodies. They are Tris and Tobias and Katniss will need their help to get back to Panem