Award-winning studio Telltale Games is springing its "Walking Dead" add-on over the next week, with the North American PlayStation Network benefiting first on July 2.
That'll be for the PlayStation 3 version, though a promised portable PlayStation Vita version is still in the works.
The Steam Network and Telltale Games' own online store will distribute the Mac and PC downloads from July 3, and Xbox 360 users are invited to join in on July 5.
PS3 owners on the European PlayStation Network get it on July 10 and wielders of iOS devices have access from July 11.
The $5 expansion acts as a side story to the game's first five episodes and introduces players to five new characters.
At least one episode of the orginal season is required, and player choices from it have an effect on the unfolding story of "400 Days."
Likewise, decisions taken in "400 Days" will carry over into a second season of the adventure game, expected to accompany the TV series's own new season this October.