
After the zombie apocalypse apparently things don't get terrible. The military stays together in some way, there are new sports born, and there are even medications to take to avoid becoming a zombie. If you played the Dead Rising 2 downloadable episode "Case West" than you noticed that a new villain was introduced to the series. Marian Mallon, the director of Phenotrans, who created zombrex which is what keeps you from having a hankering for human flesh.
When Mallon makes the remark in Case West that there needs to be another harvest for what you've done, it makes sense for another game in the series. The main character in Dead Rising 3 is Rick. He's an orphaned mechanic who is not anywhere close to Chuck and Frank West in that all he wants is to get out of the city. The city this time around is called "Los Perdidos" which means "the lost". His main goal of the game is to restore a plane and escape the city before it's destroyed by a bomb.
Supposedly an underlying theme of the game is illegal immigration. A character in the game "Red" leads a group of infected civilians called "illegals" who aren't registered by the government. At the center of the plot is Phenotrans who are connected to the outbreak in Los Perdidos. Marian Mallon returns along with a new antagonist called General Hemlock.
More information and/or a trailer may possibly be seen at the VGA's.