Akin to other Australian television programs such as Falcon Island (1981) and The Henderson Kids (1985), Secret Valley revolved in part around the attempts of a group of children to protect a ghost town and its valley from the depredations of developers. In this instance, the children form the land into a weekend holiday camp, at which they both work and play; in this sense, Secret Valley is, as Moran notes in his Guide to Australian TV Series, something of a successor to Roger Mirams's first Australian production, The Terrific Adventures of the Terrible Ten. Another group of children, led by Spider McGlurk, also live in Secret Valley (in Spider Cave), leading to a number of confrontations.
Secret Valley began as a made-for-television film, and was expanded into a twenty-four-episode series.
Moran notes that the program 'wore its Australianness well, even down to having the Secret Valley soundtrack lyrics imposed on "Waltzing Matilda".' Despite being (in part) a Grundy production, the program first aired on the ABC in Australia, and was sold into Spain, the United Kingdom (where it was a commercial failure when it aired on ITV), and the Netherlands.