The Hardy Boys/Nancy Drew Mysteries (1977)

Frank and Joe Hardy were the teenage sons of world-renowned private investigator Fenton Hardy. Snooping must have been in the Hardy blood, since Frank and Joe were always stumbling across mysterious goings-on, usually of the non-violent kind. Kidnapping, smuggling, robbery, missing persons and haunted houses were the norm in the Hardy hometown of Bayport, although their adventures often took the boys to other cities or even countries. Frank was the sensible, older brother, while Joe was impulsive and a budding pop singer. Gertrude was Frank & Joe's sometimes nagging aunt, Callie was Frank's cute girlfriend and Harry a government agent the Hardy boys occasionally worked with.