Hunter S. Thompson,left, and Oscar Zeta Acosta in Caesar’s Palace, Las Vegas, in 1971 (Photographer unknown)

At times, this hybrid of nonfiction and fictional filmmaking is as unpredictable as its subject. It centers on Oscar Zeta Acosta, an unconventional civil rights activist who became highly visible during a period of great social upheaval by shining a light on the injustices suffered by his fellow Chicanos. The film has a documentary aesthetic but bills itself as a dramatization, with actors playing the real-life historical figures yet speaking directly to the camera.

The dramatic arc of Acosta—who, among other things, inspired the infamous “Dr. Gonzo” in Hunter S. Thompson’s Fear and Loathing in Las Vegas—is framed as that of a wayward son who initially rejects his heritage, to the extent that he stops speaking Spanish. He goes on to become a Christian missionary in Panama, but those he meets there view him suspiciously, claiming he bears the “mark of the white man.” Returning to California during the late 1960s, Acosta becomes a public aid attorney, which makes him aware of the poor conditions under which many Chicanos live.

The middle section chronicles his mental and emotional breakdown, at which point he leaves California for Colorado, where a chance meeting with Thompson introduces him to the counterculture movement. However, Acosta’s desire to drive positive social change for Chicanos, and the seeming indifference of the hippies he encountered toward the social realities of brown-skinned Americans, sends him back to Los Angeles, where by 1968 he allies himself with militant activists looking for legal help.

The Rise and Fall of the Brown Buffalo has a compelling enough hero at its heart: a social justice crusader with a minister’s zeal yet burdened by demons such as alcoholism and drug addiction. But director Phillip Rodriguez, who wrote the screenplay with David Ventura, often seems to miss what is dramatically compelling about certain episodes of his life, such as Acosta’s first encounter with militant activists, who ask to see his lawyer’s license and not much else. Meanwhile, there are incidents that would have had more dramatic impact if played out, such as his many in-court antics, including at one point when he brandishes a pistol. But aside from a sequence in which he cross-examines a judge, these are mostly told to viewers.

The film also moves so briskly through Acosta’s life that it glosses over much of it. For example, he defends student protestors who staged a walkout to protest discrimination in their schools, but we never find out whether he successfully got them exonerated. The handling of his two marriages seems similarly tossed-off, especially his much-suffering second one, which we mostly hear about through passing comments by third parties. Then there’s Rodriguez’s depiction of Acosta’s ill-fated campaign for Los Angeles County Sheriff, a subplot that is hardly given any time before the narrative moves on to something else.

Although there is footage of the real-life Acosta at press conferences, he mostly appears in the film played by Jesse Celedon. While he definitely has a screen presence, it’s hard to gauge his performance with so much jumping from one scene to the next. The same could be said about much of the cast, and the filmmakers do them no favors by utilizing the green screen backdrop to morph all kinds of different backgrounds behind them, which one assumes are intended to be evocative of the psychedelic style of Acosta’s heyday, but often they come across as just cheap.

Premiering on PBS’s Voces, The Rise and Fall of the Brown Buffalo follows its title subject to an ambiguous fate, which allows various intellectuals and activists to mythologize him further. However, since the film spends precious little time on Acosta’s relationships to any of them besides Thompson, none of it feels especially poignant. Ultimately, it feels like an underwhelming tribute, but at least it depicts Acosta warts and all as someone who, despite his imperfections, managed to do some good in the world.