You and your friends had died years back and were now enjoying the afterlife. Skip forward a couple of years and there is an issue. Some idiot scientists in the living world screwed up and started a zombie apocalypse. Slowly, the dead start to rise from their graves. Thats great and all, but the thing is, you don't want to be alive again. That would mean that you would have to deal with life and school and work. So everyone is trying to cling to death, but it's not really working.