Originally released in 1970, it was one of two intertwining sequels to Farmer's previous A Feast Unknown, along with Lord of the Trees.

At the end of A Feast Unknown, Caliban and Lord Grandrith (a thinly disguised Tarzan) cease fighting each other upon learning that their personal war and indeed their entire lives were engineered by the Nine, a megalomaniacal and powerful secret society.

During the events of the book, Caliban (assisted by "Porky" Rivers and "Jocko" Simmons, analogues of "Ham" Brooks and "Monk" Mayfair from the Doc Savage stories) kills two members of the Nine, Jiinfan and Iwaldi.

Like A Feast Unknown, The Mad Goblin contains many elements in common with Farmer's Wold Newton family concept, primarily the presence of characters based on Doc Savage and Tarzan.

Farmer himself said that it was best to "let the reader decide", but some Wold Newton fans have taken it upon themselves to explain the apparent discrepancies.

This book was volume twenty-three in the "Worlds of Philip José Farmer" series of Russian collections.