Lego Left 4 Dead 2

An unknown pandemic hit the United States, and this virus has turned the majority of the population into bloodthirsty creatures: the "infected," which attack any healthy person. The government has declared martial law and decided to group the population in major cities, under the protection of the Army. The situation then gets out of control. The concentrations of survivors being an easy target for infection, most of the uninfected population is massacred.
The government then orders the creation of a secured area, being the only place still under the protection of the army and entirely protected from infection, having gathered the last survivors of the pandemic. In this context, the four heroes: Coach, Nick, Rochelle, and Ellis, are trapped in downtown Savannah, Georgia.