Prison Architect's next expansion will arrive on October 11th, just in time for spooky season. The timing is significant because the DLC is called Undead and its main new feature is zombies.
Here's a trailer:
With the expansion activated, there will be several methods for the undead infection to spread in your prison. An inmate can get spontaneously sick, the dead can rise via the graveyard, and once you've got a zombie wandering about, they can bite and infect others.
To help you fight the undead plague, the DLC also introduces the "Bounty Hunter Emergency Service", who can be summoned to assist inmates and guards, as well as new traps and tools, including zombie lures and a chainsaw. Groovy.
I've written multiple times that I appreciated Prison Architect's careful balance when it came to gamifying the grim subject of prisons, whereas I wasn't a fan of the post-Introversion DLC, which has often seemed to upend that balance in favour of leaning towards hijinks. Y'know, prison islands, weed farms, "criminally insane" inmates, that sort of thing. I'm actually OK with this wholly wild DLC, however, because zombies are outright fantasy rather than an attempt to turn various forms of prison labour into a jolly good time.
You can find out more about the Undead DLC over on Steam. It'll cost £2.09/$3 when it launches, and come alongside a free update which adds Corgis and Siberian Huskies to the game.