never done one of these before but you get this when you do all the gangs. There are four. 2 are story related, and 2 are optional.
For the woodsman gang, you start it by solving The Mystery of the Black Box investigation. The culprit is the hooded man.
For the Spinach Berserkers
You start with The Mystery of the Evening Run, the culprit is the Long haired man.
This is a link that has detailed info on the two optional ones, as well some pictures(since i dont know how to add pictures in a solution).https://guides.gamepressure.com/this-is-the-police-2/guide.a...