Drive to the gate of Lost Lake to start this mission. Ride with Iron Mike to Sherman’s Camp afterward. This mission will be a lot easier if you managed to clear the Infestation zone in the area. After arriving at the town, follow Iron Mike to the preschool for a cutscene. After the scene, grab the key from the corpse in the corner of the room.
Loot the crafting materials lying around then exit the preschool. Follow Iron Mike once again as he leads you to the courthouse, a few steps away from the school. Wait for Mike to open the locked door then continue upstairs. Open the marked door for another cutscene and the next mission will start automatically.
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