“Pulp Fiction” director Quentin Tarantino also has a small role in “Sin City,” appearing in a single scene as an unnamed character with an unnerving monologue. He was paid a single dollar for this acting credit, Variety reports. Clearly, Tarantino wasn’t making an appearance for the money — I would guess that he joined the cast because “Sin City” aligned with his vision as a filmmaker while being completely unique in tone and aesthetic.
Since Willis and Tarantino had worked together on “Pulp Fiction,” the set of “Sin City” was a bit of a reunion for them. Willis did not appear in the same scene as Tarantino, but the onscreen cameo was not the filmmaker’s only role on set. Tarantino is also credited as a guest director on “Sin City.” “He put his stamp all over it,” Rodriguez said in a behind-the-scenes featurette (via The Archives of Kino).
Miller appreciated the distinct flare that Tarantino brought to the film. He directed in “a completely different style than Robert [Rodriguez]’s,” which is surprising given that, as Miller admits, “the three of us share so much in terms of a pop-cultural sensibility.” Miller recognizes that they each take vastly similar references and put an entirely unique spin on them. However, “given the enormity of the three egos in the room,” their working relationship was “shockingly harmonious.”
Two modern classics, “Sin City” and “Pulp Fiction” both call upon the great films of yesteryear to produce something entirely new and exciting. The flashy style of “Pulp Fiction” paved the way for the edgy experimentation of “Sin City,” and Tarantino’s appearance is a touching nod to his undeniable influence.
Source : https://www.slashfilm.com/936997/sin-citys-set-was-home-to-a-small-pulp-fiction-reunion/