The fictional characters of The Big O anime series were designed by series creator Keiichi Sato, who also designed characters for the City Hunter series. Because of union rules, most of the English voice cast for the first season were credited under pseudonyms; the only ones who used their real names were Lia Sargent (R. Dorothy Wayneright), Wendee Lee (Angel), Michael McConnohie (Schwarzwald) and William Frederick Knight (Gordon Rosewater).
Voiced by: Mitsuru Miyamoto (Japanese); Steven Blum (English)
Roger Smith (ロジャー・スミス Rojā Sumisu?) is the series protagonist. He is the Negotiator (ネゴシエイター Negoshieitā?). His job entails finding a resolution for the troubles of Paradigm City, the "City of Amnesia". He'd negotiate anything for anyone, but he is a professional and expects the parties to behave professionally. Despite this, he displays a certain aversion to the Paradigm Corporation, and takes the jobs he gets from them only if they happen to involve a threat to the city itself or are of personal interest to him. When memories betray the people and force them to reawaken monstrosities of the city's past, Roger's only option is to fight back with a monstrosity of his own, the black megadeus Big O. The character, originally envisioned as a private eye, shows influences from Batman, James Bond and Daisaku Kusama from Giant Robo.