Photo: CBS/NBC

51 years ago, after a failed pilot and thanks to the good will of comedic legend and astute producer Lucille Ball, Star Trek: The Original Series premiered. At its best, The Original Series married hard science fiction, expansive mythology, a sincere interest in diversity, blistering intelligence, and belief in the good of humanity. I’m not sure creator Gene Roddenberry realized how grand a franchise Star Trek would grow into, but all these years later, it now includes action-oriented blockbusters, comic books, an animated series, parodies, homages, and a potent place within the cultural imagination. But Star Trek has always been at its best on television, where its verbose, philosophical leanings have the chance to truly flourish. In honor of the latest addition to the franchise, Star Trek: Discovery, which premieres on CBS on September 24, here’s a ranking of every live-action Star Trek series from worst to best.

5. Star Trek: Enterprise

Star Trek: Enterprise is perhaps the most maligned series in the franchise’s history, so much so that it’s credited with Star Trek’s long absence from pop culture until the sleek J.J. Abrams reboot. But watching Enterprise proves that the truth is a bit more complex: The series took a long time to find its feet, only hitting its stride in its final season with episodes like the two-parter “In a Mirror, Darkly” and “Borderland” — which featured mainstay Brent Spiner as Dr. Arik Soong, the grandfather of the man who created Data (the android played by Spiner in Star Trek: The Next Generation) — only to end with one of the most infuriating series finales I’ve witnessed. Enterprise takes place 100 years before the USS Enterprise’s five-year mission involving Kirk, Spock, and the beloved crew from The Original Series. The crew is led by Scott Bakula’s Jonathan Archer, a dedicated and bold captain with a dash of space-cowboy flair (and the curious wrinkle of his character’s prejudice toward Vulcans). Enterprise ultimately failed in its uneasy relationship with canon in early seasons and poor characterization. It made the mistake of looking backward, something that has plagued the franchise ever since.

4. Star Trek: Voyager

At first blush, Star Trek: Voyager had all the makings of an excellent series. It undoubtedly had the best premise: The USS Voyager is thrust into the unexplored Delta Quadrant alongside a terrorist organization known as the Maquis. The two crews reluctantly join forces after great losses, as the entire medical crew is dead, with a holo program picking up the slack. Worse yet, it will take them 75 years to journey. There is no Federation to help them and enemies lurk around every corner. Voyager was one of the most diverse series in the franchise’s history, thanks to characters like the half-Klingon, half-human Latina character B’Elanna Torres played by actress Roxann Dawson, fan favorite Seven of Nine (played by Jeri Ryan), former Maquis turned First Officer Chakotay (Robert Beltran), and of course, the steely eyed woman at the helm, Captain Kathryn Janeway (Kate Mulgrew). Unfortunately, Voyager reigns as the most infuriating and creatively haphazard Star Trek series for how it squandered such a great premise. Voyager was saddled with several annoying and pointless characters, uneven storytelling, and a misguided dedication to the Prime Directive, despite the crew being far from Federation space. Worse yet was the characterization.

Captain Janeway was one of the greatest examples of how diversity and representation is hollow without meaningful characterization. Mulgrew loaned a sly sense of humor and flinty nature, but the character lacked consistency, often acting hypocritical in ways that didn’t make sense. Many of the other characters lacked a strong throughline: Some were annoying spectacles (Neelix, I’m looking at you), while others like B’Elanna and Seven of Nine were undercut by relationships that lacked chemistry. Yes, Seven of Nine was a fascinating character (despite being treated primarily as eye candy) who continued the franchise’s interest in the question, “What is humanity?” Unfortunately, her entrance in the fourth season led to an unbalanced series, as already uneven characters were marginalized further. I may sound a bit harsh on Voyager, but that’s only because its flashes of brilliance were truly noteworthy. When Voyager left behind its conservative approach to its premise, it gave us stellar episodes like “Year of Hell Part 1 and 2” and “Timeless,” proof that the show would have been remarkable if it were a bit more audacious.

3. Star Trek: The Original Series

What can be said about Star Trek’s first iteration that hasn’t already been said? Although it lasted only three seasons, The Original Series laid the foundation for everything to come, spawning one of the longest-running, most important fandoms in television history. Some of Star Trek’s most important tenets began with The Original Series: its intellectual curiosity, the Prime Directive, its use of alien cultures to interrogate modern concerns, and its devotion to diversity. It was nothing short of revolutionary, granting TV a few of the first Asian and black characters who weren’t reduced to stereotypes. Keep in mind the show premiered a few years removed from the March on Washington and the Civil Rights Act of 1968. But the worth of The Original Series goes beyond that: The five-year mission of the USS Enterprise introduced us to standout characters like Lieutenant Uhura (Nichelle Nichols, who was once convinced by Martin Luther King Jr. to stay on the show) and my personal favorite, First/Science Officer Spock (the ever-graceful and nuanced Leonard Nimoy). The cast chemistry, sincerity, brilliant stand-alone episodes, and subsequent films like The Wrath of Khan led The Original Series to root itself deeply in American culture.

2. Star Trek: The Next Generation

Watching television while my mother braided my hair was a nightly ritual I learned to cherish. These are some of the few childhood memories that I hold dear. One series we watched together was Star Trek: The Next Generation. I’m not sure if it was Commander William Riker’s rakish grin, the stalwart nature and intelligence of Capt. Jean Luc-Picard (who inspired me to pick up the daily habit of drinking tea), or Deanna Troi’s somewhat hilarious confrontations with her mother (played by Majel Barrett, a.k.a. the First Lady of Star Trek for her previous appearances in the franchise and being the voice of the computer, along with being Roddenberry’s wife), but soon enough I was obsessed. Still, my love for The Next Generation is not nostalgia. It took the traditions of The Original Series to interrogate them deeper. Over the course of seven seasons, The Next Generation fine-tuned everything that made The Original Series so beguiling: an intellectual curiosity, political discussions, a charming cast that came across truly as family, and dynamite two-part episodes and cliffhangers.

The Next Generation also suggested a hopeful future for humanity that is somewhat hard to imagine: a future on Earth free of racism, sexism, or classism as the Federation keeps peace and explores the galaxy. Perhaps it’s this hopefulness that made the show the most successful Star Trek series during its airing. These days, it would be easy to disregard TNG as a relic of a television era when a lack of stylistic visual flair and a dedication to stand-alone episodes was the norm, but the series has a startling intelligence and empathy that illustrates why the franchise was so potent in the first place.

1. Star Trek: Deep Space Nine

“So, I lied. I cheated. I bribed men to cover the crimes of other men. I am an accessory to murder. But the most damning thing of all … I think I can live with it. And if I had to do it all over again, I would.” Captain Benjamin Sisko said these words during one of the most incisive, politically complex episodes in the entire Star Trek franchise, “In the Pale Moonlight.” This monologue, delivered in actor Avery Brooks’s rich baritone voice, encapsulates what made Deep Space Nine unlike anything before or since in Star Trek history. Though blessed by Roddenberry before his death, DS9 benefited from disregarding certain ground rules, like how the crew wasn’t supposed to have longstanding conflicts. Perhaps more important, it balanced each season with great stand-alone episodes enriched by longform arcs — becoming one of the first TV shows to do so. With Sisko, it also introduced Star Trek’s first black captain (although he began the show in a lower position). The show even reintroduced TNG characters like Lieutenant Worf, granting them further depth and dimensions.

If earlier iterations of Star Trek granted a utopian glow to modern humanity, Deep Space Nine revealed the price of maintaining such progress. It was darker, yet never without purpose. It was more nuanced in terms of portraying relationships between adults. DS9 used its premise of Sisko and his ragtag crew on a space station to interrogate the perils of war, the power of religion, terrorism, and the price of freedom, all while creating one of the most poignant depictions of black fatherhood that has ever appeared on television. It also had some of the best acting and direction within the franchise’s history. Deep Space 9 was Star Trek at its most artful and impactful. More than that, it was science fiction at its most incisive.