The Darkness Devil's debut panel may be connected to a photo of the Apollo 1 astronauts praying over a miniature space shuttle.
The manga Chainsaw Man by Tatsuki Fujimoto is known for its over the top action and brutal scenes of gore, yet it has always maintained a sense of thematic layering beneath its eye-catching panels. Chainsaw Man tackles various themes including love, change, and most of all, fear. Nowhere is that clearer than the series’ most jaw-dropping panel, which makes no attempt to hide Fujimoto’s message about fear.
In chapter 64 of Chainsaw Man, the international assassin known as “Santa Claus” succeeds in using her former apprentice to contact and fulfill a contract with the Darkness Devil. Since the entire cast of characters was transported to Hell prior, the Darkness Devil is able to manifest itself completely and appears before the Devil Hunters and Santa Claus. As it makes its debut, the Darkness Devil is preceded by a hall of bisected astronauts with their hands joined in prayer. This Chainsaw Man image is horrifying and may seem completely random at first glance, but it likely references an extremely dark event in human history.
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It's possible this page is a reference to an image of the Apollo 1 crew, consisting of Ed White, Gus Grissom, and Roger B. Chaffee. In this photo, the three astronauts hold their hands in prayer as a joke over a miniature of the Apollo 1 space shuttle. On January 27, 1967, these three astronauts were all tragically killed when the shuttle caught fire during a test launch. It seems unlikely that Fujimoto using the imagery of praying astronauts is a coincidence, especially when it comes to the Darkness Devil. All devils in the world of Chainsaw Man are powered by the fear that humanity has for the aspect of reality they represent, and the image of fallen astronauts is seemingly intended to evoke the fear of space and, by extension, darkness. The explosion and destruction caused by a failed space shuttle test invokes all of humanity's fears associated with space - the idea of being trapped, being alone and being struck down in the attempt to even reach a void which will ultimately consume everything.
Space is treated as the final frontier yet is also the ultimate darkness that surrounds humanity at all times. The Darkness Devil being heralded by the appearance of fallen astronauts is a warning. Fujimoto uses the image of praying astronauts to drive home the idea that space and the horrors it holds are not a matter to be taken lightly. Metaphorically, Chainsaw Man's astronauts are adventurers into darkness who hoped for the best and found the worst. Space contains the unknown, and the Darkness Devil's entourage represent the idea of humanity's lack of control of the vast night beyond their planet, whether it references the Apollo 1 photo or not.
Chainsaw Man’s most famous panel is directly connected to the themes of fear present in the manga. The most common devils in the series are ones that represent and manifest weapons such as bombs, crossbows, and katanas, yet the truly powerful devils are more abstract in nature. These include the Four Horsemen Devils of Conquest, Death, War, and Hunger as well as the Darkness Devil itself. The fear of darkness is bound up in the human experience, and seeing as how the Chainsaw Man’s Darkness Devil is the terrifying culmination of that fear, it makes sense for it to be represented by referencing a real-life tragedy that saw those fears come true.
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