SEASON PREMIERE: It’s the start of Season 4 for this inventive and enjoyable zombie series, which is about as light as The Walking Dead is dark. Rose McIver stars as Liv Moore (get the spirit already?), a woman who works as a morgue attendant while solving crimes on the side – and solving them by ingesting samples of the brains of murder victims, temporarily absorbing their personalities, and using their trace memories to solve that person’s pre-corpse death. At the end of last season, the existence of zombies was revealed to the public. This season, as with the artificial plasma drink marketed to parts of the vampire population in True Blood, the entrepreneurs on iZombie begin offering a concoction of synthesized brains.