But they're already dead so how can they survive?

Whoa, yet another zombie movie from George A. Romero!

Weirdly, "Survival of the Dead" will be available via video on demand BEFORE it hits theaters.

I think the plot sounds interesting, though...people escape to an island to try and cure their zombified relatives. Haven't really seen that angle before. Well, we've seen the island angle, and the trying for a cure angle, but the combination is interesting.