More than just a deep look at the history of tango, or even its subjects’ influence on the art, Our Last Tango (2015) is an evaluation of Maria Nieves’ and Juan Carlos Copes’ rocky relationship that persisted for five decades through a mutual love of dance.

“If I die and were to be reborn, I’d do everything the same again,” Nieves says early in the film, and pauses before adding, “...except for being with Juan.”

That quote sets up everything the film is about. Although as the story unfolds, it’s made clear neither Nieves or Copes would have been likely to accomplish what they did without each other’s partnership, as complicated and heartbreaking as it was.

When the two first met, Copes couldn’t even dance. Their appetite for one another boiled and they became dancing partners - a title they would share for decades, into the late 1990s. But their romance died long before the shoes came off. It waned through Copes’ admittedly persistent infidelities and commanding behavior, ultimately hitting a barrier there was no turning back from. Their dancing, which was originally fueled by love and romance, became fueled by hate. They stopped looking at each other when they moved. But they continued to dance, because neither ever found a partner better suited for them—and above all, both loved the tango.

Our Last Tango digs into this concept deeply. The two never stopped being a well-regarded performance couple, even when they couldn’t stand each other. The divide between emotional and artistic love, when in the hands of professionals, should be unknown to the audience. The tango is a dance that thrives on passion; requires it. An indifferent tango is a failed tango. But Nieves and Copes prove the passion tango perceives as interpersonal doesn’t have to come from an emotional connection between its performers, but rather can (and perhaps should) be between the dancers and the artform itself.

“We cursed each other when we danced,” Nieves recalls at one point. The tango itself, a beautifully unified movement of playfulness, is deeply sentimental and expresses the masculinity of the man and the soft affectionateness of the woman. The two become the musical instruments creating the music, each offering its own sound and emotional value. Neither is dominant of the other, and neither is replaceable.

Such necessary chemistry is what secured the Nieves-Copes partnership despite their personal problems. Our Last Tango interviews the subjects separately, indicating they’re not on good enough terms to even be interviewed together, yet both regarded the other as the only partner ever suitable for perfect tango. Beyond the superficial relationship drama of the film, the lasting message speaks to the heart of the dance. Nieves and Copes want people to understand the importance of tango in their lives and how their love for the style trumped all other emotions. Fortunately, between the keen interviews conducted by the film’s dancers and their stunning choreographic journey through Nieves and Copes’ evolution, that’s exactly the sentiment it leaves behind.