Like New Mexico in Breaking Bad or that comical Minnesotan drawl in Fargo, the use of color in Spike Jonze’s Her (2013) is so distinctive, it could almost be its own character.

In Her, the future is not gunmetals and black latex, but rather, muted shades of earth tones and khakis. What stands out are the vibrant reds and yellows occasionally thrown at us via protagonist Theodore’s (Joaquin Phoenix) shirts in a see of urban futuristic Angelenos.

Colors have been utilized for dramatic purposes since Dorothy first unveiled Technicolor with her red shoes. In L. Frank Baum’s original story, the slippers were silver, some say another political motif in Baum’s consumer allegory. The producers of the film decided to turn them red, to better show off the new invention of color film. Even pre-Technicolor film utilized color in some form or the other. According to David Cook in A History of Narrative Film, some filmmakers in the early days tinted or hand-painted each frame to reproduce the look of real-life color.

The way color is used in Her is perhaps more in line with 500 Days of Summer than the flashy Wizard of Oz or black and white aspirants. In 500 Days of Summer, color is used in a way as an emotional resonance. Titular Summer always wears blue; it’s her calling card. When Tom meets Autumn at the end, she’s wearing red: the opposite of Summer.

Ironically, the color blue was completely omitted from Her. According to the movie’s costume designer, Casey Storm, “It’s avoiding what’s traditionally in the future. Hoyte [van Hoytema, the cinematographer] did that. He became excited about the absence of blue as a visual reference.”

But do colors denote emotions in Her? The use seems so in-your-face, so obvious, that it must mean something. And indeed, whole online forums have been devoted to unpacking the meaning behind each color choice in Her. The mild-mannered, noncommital Theo is always in the most solid, declarative red shirts; but perhaps it’s more of an aesthetic decision, rather than a character reflection. Those bright red shirts are a visual separator, setting our protagonist distinct from the hoards of other future city dwellers.

On the other hand, the emotional resonance is there. According to production designer K.K. Barrett, the red is there because, “It seemed to fit Theo’s temperament—his passion, compassion, loneliness, and hopefulness. Red was the perfect thing to use in the movie and we did it every which way we could.”