The opening sequence of "The Big Combo" effectively sets the film noir tone and introduces key elements:
1) An aerial establishing shot presents the city as a dark labyrinth engulfing the characters in mystery. Panning shots reveal a nighttime city illuminated by sparse lighting, connoting potential criminality.
2) A woman runs frantically through dark alleys, chased by two men, establishing her as the "femme fatale" and creating suspense about her pursuers' motives.
3) The complex city streets function as a maze, trapping the characters, consistent with the film noir theme. The woman ultimately asserts control by demanding her pursuers stop for food