The film is based on a story,
Sa mga Kuko ng Liwanag (lit. "In the Claws of Brightness'"), written by
Edgardo Reyes. It was originally serialized in
Liwayway magazine from 1966 to 1967, and was later published into a novel. The adaptation into film originally started out life as a writing exercise. In 1970,
Ateneo de Manila graduate
Clodualdo del Mundo, Jr. re-enrolled in his alma mater to take a short course in film writing. There, he wrote
Pepot Artista (a screenplay he would later revisit in the 2000s). Del Mundo finished his script for
Pepot Artista, which was supposed to be a major assignment, by the middle of the semester; earlier than what was expected. His professor, Nestor Torre, requested him to make another screenplay as way of filling in the extra time. Because he had just written an original screenplay, Del Mundo tried his hand at adapting a literary source for a change. He chose Reyes' story, already a novel by then, as the subject for his next assignment. After turning in the
spec script, Del Mundo completed his course and relocated to the United States to continue his studies at the
University of Kansas in
Lawrence, Kansas.
Mike De Leon, grandson to
Narcisa de Leon of
LVN Pictures, had directed one short film and intended to expand his role in the film industry, namely as a producer. De Leon had just put up a new production company,
Cinema Artists, and was in the process of seeking out projects. Eventually, De Leon remembered of Del Mundo's trial adaptation. Having been friends since their days at
Ateneo de Manila, De Leon contacted Del Mundo with the idea of producing the latter's
spec script. Del Mundo, who just returned from his four-year course in Kansas, gave De Leon his blessing and agreed to further polish the screenplay. "It was the right time," Del Mundo recalls.
Lino Brocka, who had just received acclaim for his previous work,
Tinimbang Ka Ngunit Kulang, was approached by De Leon to direct the adaptation. Brocka took this as an opportunity to create a commentary about urban poverty amidst the
Marcos dictatorship and included homosexual themes not present in the original source. "Brocka understood the popular audience well," Del Mundo says. "He suggested additions to the screenplay [of
The Claws of Light] to make it more commercial. It was fun working with him, although he was quite emotional." The production title was eventually changed from
Sa mga Kuko ng Liwanag to
Maynila, sa mga Kuko ng Liwanag (lit. translation:
Manila in the Claws of Light) to emphasize on the setting of the story. An independent production,
The Claws of Light was produced with a modest budget for Cinema Artists. Principal photography occurred in 1974. The film was shot on actual locations around the vicinity of Manila, to better capture the authenticity of the city.
Jay Ilagan, who had previously acted in Brocka's films, initially played the lead role of Julio Madiaga. Having already participated in several days of shooting, Ilagan was asked to drop out of the production when Brocka became dissatisfied with the performance. Upon viewing the dailies, Brocka was convinced that Ilagan, who had a very healthy appearance, did not meet his vision of Julio—a pitiful vagrant that wades in and around the urban gutters. The role was re-cast with newcomer
Bembol Roco in the part. Prior to this film, Roco's only foray in to acting was a relatively small role in Brocka's previous film,
Three, Two, One. For this film, he was credited under his real name of Rafael Roco, Jr.
The Claws of Light marked what would become the first lead role for Roco. To play the love of Julio's life, Brocka chose
Hilda Koronel. For the role of Ligaya Paraiso.
Lou Salvador, Jr., a former
matinee idol famous for playing angst-ridden romantic leads in LVN's teen rebel pictures, was cast against type as the wise and sympathetic Atong. Character actor Tommy Yap was cast as the rarely-seen antagonist, Ah-Tek. Yap would later appear—albeit less significantly—in Brocka's
Insiang, alongside Koronel. The majority of the actors that round out the film, such as Tommy Abuel and
Joonee Gamboa, were veterans of both the stage and radio. == Reception ==