“Johnny Z” (** out of four) was a spare-parts action thriller about the title half-human/half-zombie (Michael Merchant) who is trained by a martial arts master (Felix Cortes) and then subsequently seeks vengeance on the ruthless and evil corporation that created him leading to bloody war. Congenitally derivative story borrows plot threads from too many other films to count but is overall well-paced and Merchant’s strong performance helps to keep it watchable. Not all that different from “Johnny Mnemonic” with Keanu Reeves but is at least far better than that 1995 disaster.