who wrote the script for the aforesaid former work?
Paul Dehn
Beneath the Planet of the Apes
Beneath the Planet of the Apes is a 1970 American science fiction film directed by Ted Post and written by Paul Dehn. 
all the planet of the apes in order "Beneath the Planet of the Apes", "Escape from the Planet of the Apes", "Conquest of the Planet of the Apes" and "Battle for the Planet of the Apes". what kind of a work is it? It is an American science fiction media franchise consisting of films, books, television series, comics, and other media about a world in which humans and intelligent apes clash for control.
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Beneath the Planet of the Apes [SEP] Introduction
Beneath the Planet of the Apes is a 1970 American science fiction film directed by Ted Post and written by Paul Dehn. It is the second of five films in the original "Planet of the Apes" series produced by Arthur P. Jacobs. The film stars James Franciscus, Kim Hunter, Maurice Evans, and Linda Harrison, and features Charlton Heston in a supporting role. In this sequel, another spacecraft crashes on the planet ruled by apes, carrying astronaut Brent who searches for Taylor and discovers an underground city inhabited by mutated humans with psychic powers. "Beneath the Planet of the Apes" was a success at the box office but met with mixed reviews from critics.