I believe that genre mash-ups can work. They certainly do in fiction, and I think they can work on screen. It's just there's not many successful examples. That said, the blend of the Western and the zombie movie had me excited about writer/director John Geddes' Exit Humanity when I saw it at this year's ScreamFest.
Combining the Western genre with zombies, Exit Humanity follows Civil War soldier Edward Young (Mark Gibson), who keeps a diary of his activities as he travels the land following an unexplained zombie outbreak. The first half quarter of the movie sets up the narrative structure of the diary, which is broken up into chapters throughout the movie narrated by (presumably) an elder Young (Brian Cox), and the dire circumstances of Young's life following the Civil War. It's a sober and harrowing beginning, revealing a dark and serious tone, but one that the movie inevitably can't support.
Westerns are often about revenge, or about men who's motivations aren't exactly clear. Gibson's Young doesn't exactly fit into either category. Sure, he's looking for meaning to his life in the wake of a zombie apocalypse, but it doesn't seem like he wants to take vengeance on any and every zombie like the Western genre elements might suggest. When he eventually meets up with Isaac (Adam Seybold), he is given a purpose by joining the effort to save Isaac's sister Emma (Jordan Hayes) from a group of soldiers (Bill Moseley and Stephen McHattie amongst them) that are instantly made out to be the antagonists of the film. While the rescue operation seems like it would be the ticket for Young to find meaning in his life again, it's only a portion of the story. Young eventually travels with the siblings, meeting up with Eve (Dee Wallace), a woman with a dark past.
At this point, I'm not sure whether Exit Humanity is a Western or a zombie movie. Young eventually bonds with the group, despite learning something about Eve's past that should have instantly sent him over the edge, and Moseley and McHattie return to solidify themselves as the movie's villains in a way that feels more than a little forced.
I applaud Exit Humanity for doing what they did on their budget. Filming a period piece that is a Western and a zombie movie was certainly ambitious. The movie brings in a mostly solid cast, though Moseley and McHattie's roles were limited and Wallace borders on over-acting about 90% of the time. The zombie make-up looks pretty good, and, if the budget could have afforded it, some of the sequences that ended up being animated would have been nice to see in live-action. Oh, did I mention that there are animated sequences? No? Well, there is. In fact, most of the heavy, narrated exposition is covered by animation.
Ultimately, Exit Humanity buckles under the weight of its high ambitions. It is absolutely better than most of the straight-to-DVD zombie schlock out there, but giving the lead character a directive rather than watching him wander around looking for purpose, would have made a more enjoyable movie.