US Government builds a wall around Seattle...they dont want zombies getting out and the zombie government wants to keep them in the city. City also becomes only reliable way to get brains w/o murdering/robbing morgues. Seattle basically becomes a world power because of the zombies, but the humans living there also act as a human shield (ie, they cant nuke the city w/o killing hundreds of thousands of people). Major is on the side of the Merc company, Liv still hates them. 1st episode of next season will show what happens with Ravi. They confirmed that there are side effects, which seems to suggest the vaccine might not work fully. Seattle PD handles human murder investigations, Merc company handles zombie murder investigations. All the homicide detectives at the PD get zombie partners. Blaine makes a shitload of money lol