The series re-imagines the comic book's main characters (Martin Mystery and Diana Lombard) as a 16-year-old step-siblings. They work for a covert organization "The Center", which covertly protects the people of Earth from supernatural threats. As a covert organization, their work must be kept secret and for this reason, anyone who comes too close to their missions will have their memories of the event erased. Not everyone who works for the organization is human. Billy (a small, green-skinned alien), is actually one of Martin's best friends. Java (a caveman from 200,000 years ago), works as a janitor at Diana and Martin's school. As far as "The Center" is concerned, Martin's vast knowledge of the supernatural and his remarkable intuition compensate for his poor personal hygiene and huge ego. Diana loves him very much but she resents these flaws at times, as Martin often does not seem to understand the seriousness of his missions.