The premise of the show is inspired by Le fugitif (1963), Blade Runner (1982), and Frankenstein (1931) where a character that's deemed a threat is hunted down and feared despite having good intentions.
Zeta originally appeared on Batman, la relève (1999) in the episode titled, Zeta (2000). Alan Burnett wanted to do an episode where Batman fought a robot and handed it off to one of the writers on the show, Bob Goodman following a conversation with Burnett regarding a movie idea Goodman had been formulating involving a man keeping a hostage in his basement. Bob came up with the Zeta idea by turning the robot into a good guy as an homage to his love of classic monster movies such as Frankenstein and in an attempt to keep with the theme of humanity being more monstrous than the monsters. Originally, there was no discussion at the time of doing anything after the episode was complete, but once the script was done, audio had been recorded, and the episode was finally in pre-production, Goodman realized that the door was now open to expand Zeta's story and give him a series of his own.
This is the only series in the DC Animated Universe in which the protagonist was not a character from DC Comics. Zeta made his first appearance in Zeta (2000).
Agent West is voiced by Michael Rosenbaum, who ended up voicing The Flash/Wally West in the TV series' La Ligue des justiciers (2001) and Justice League Unlimited (2004). Given that both characters have red hair, their last name is West, and are both voiced by Rosenbaum, Agent West might actually be a relative of The Flash/Wally West.
This show introduces Doctor Eli Selig who is Zeta's creator and the former head of the government's Infiltration Unit Program, who knows Zeta's abilities and limitations better than anyone else. Zeta and Ro are constantly trying to find the elusive Doctor Selig in order get him to convince Agent Bennet and NSA that Zeta is not a threat.