In 1957 Villius joined Swedish Radiotjänst (now Sveriges Radio), Sweden's national public radio corporation, and began making popular historical documentaries and programming until he moved to Sveriges Television (SVT) in 1966.

It was at SVT that Villius began working with TV-producer Olle Häger, a very productive collaboration that would span some two decades.

During the 1980s and 1990s, Häger and Villius produced several popular documentaries like Fyra dagar som skakade Sverige[1] ("Four days that shook Sweden") in 1988 about the Swedish "Midsummer crisis" during World War II and Raoul Wallenberg - fånge i Sovjet[1] ("Raoul Wallenberg - prisoner in the Soviet Union.")

Other than his dedication to entertaining and educating, Villius was most famous for his narrating both his own and others' documentaries, and his soft Kalmar-accent is instantly recognizable to millions of Swedes (even to those who do not know his name).

His voice has almost become a concept of its own, intimately associated with serious educational programming and spawning many parodies (e.g., in TV-commercials) and imitations among comedians.