from what i gathered its about the events as the apocolypse began and the cast are not "survivors" like in TWD proper. They are people who dont seem to stand much chance of making it.
Some people have said it's crap others have said its good, I'll definately have to get it, it'll be like TWD prequel or something i guess, just with a bunch of characters who dont seem to have what it takes to survive, i guess that could make it seem more realistic in some ways. How many everyday people would really turn out to be warrior super heroes like Darryl and Michone i wonder, it would be interesting to see what happens to a bunch of nerds and wimps and drug addicts like the cast in the fear the walking dead are said to be. Merle with his Terminator arm was into his chrystal meth but he was a survivor, half crazy too, slashing open all the matresses in the prison in case any prisoners had stashed drugs in there, a dangerous character to have as your friend let alone your enemy.