Enterprise is the most sharply criticized Star Trek series ever produced, but despite its many disappointments the show still mustered some genuinely entertaining and intriguing moments of greatness. We highlight the five best Enterprise episodes below.

5. In a Mirror, Darkly [Video clip]

Every now and then, it’s simply obvious that the cast and crew of a television show are having fun, and that enthusiasm makes for a better a product. Case in point: The Enterprise take on the Star Trek Mirror Universe, which is also a fan-service callback to the original series episode “The Tholian Web.” This episode not only reveals the secret origin of the evil Terran Empire that dominates Mirror Universe continuity, but it allows Scott Bakula and friends to play the unrepentantly evil versions of their familiar characters and to have an obvious ball doing it. Moreover, detachment from the regular series continuity — this two-parter never intersects or influences the main Enterprise storyline on any level — allows the writers to rattle off not just a gleefully malicious and fatal series of unexpected double-crosses, but also work in some of the most satisfying and coherent mythology gags that Enterprise ever displayed. A guilty pleasure episode for all involved.

4. Carbon Creek [Video of full episode]

A charming character study episode that is a conscious — and self-admitted — throwback to classic The Twilight Zone stories from the 1950s and ’60s. T’Pol recounts the story of her great grandmother’s time on Earth a century before historical First Contact. She and her crewmates were stranded for months in a rural 1957 Pennsylvania mining town after their survey ship crashed. Unsure if rescue would ever come, the Vulcans were forced to violate their own analog of the Prime Directive to survive, disguising themselves as humans and becoming members of the small community. Jolene Blalock plays T’Pol’s own ancestor who befriends a bright but poverty-stricken young boy, and the period piece is a quaint, self-contained story of compassion and friendship as experienced by supposedly emotionless aliens. As fine a standalone episode as you’ll find in Enterprise.

3. Demons/Terra Prime [Video clip of “Demons” / Video clip of “Terra Prime”]

The two-parter that producer Manny Coto considers the “real” series finale of Enterprise sees guest star Peter Weller steal the show as a xenophobic terrorist intent on banishing all non-humans from Earth, even as potential founding member-species of the Federation are on-planet to discuss whether an alliance is worthwhile. Weller has two weapons in his arsenal: A space cannon capable of destroying any city or ship in the solar system, and the poorly cloned and slowly dying infant daughter of T’Pol and Trip designed to illustrate how non-viable interspecies relations really are. Weller and Archer square off as two men devoted to diametrically opposed visions of humanity’s future, and the episode demonstrates the lengths to which each will go to realize their respective dreams. The world-spanning military conflict is deftly balanced with the private tragedy of the Vulcan-human hybrid child, bringing together a solid conclusion to Enterprise, no matter what embarrassing so-called “finale” may have followed.

2. Cogenitor [Video of full episode]

Star Trek is at its best when it uses sci-fi allegories to tackle real ethical quandaries, and this chapter of Enterprise is a proud contributor to that tradition. The crew makes diplomatic contact with the Vissians, an alien race with similar exploration ambitions as Starfleet, and Archer encourages his officers to spend time with their Vissian counterparts. Trip discovers that the Vissians are a tri-gendered species when he meets his fellow chief engineer, the engineer’s wife, and the couple’s indentured cogenitor — the slave gender that makes Vissian reproduction possible. Trip is immediately troubled by the low-caste servitor status of the cogenitor who is so poorly thought of by the Vissians it doesn’t even have a name. Trip’s sympathy towards the cogenitor gives it hope for a better life, which the Vissians refuse to provide — souring relations with the Enterprise crew. The ethical debate ends not with a tidy conclusion, but rather a thoughtful and tragic object lesson in the harsh necessity of the still-forming Prime Directive. Enterprise was often criticized for its unwillingness or inability to reach the high standards of Star Trek, but “Cogenitor” is one of the rare occasions where it clearly makes the grade.

1. Similitude [Video clip]

The central moral trap posed by the best Star Trek episodes is a simple, if insoluble, question: When is it right or fair to trade one life for another? “Similitude” grapples with that question by attacking a real and very current ethical issue: cloning sentient beings simply as fodder for spare body parts, often at the cost of the clone’s life. In this case, in the wake of a life-threatening brain injury to Trip, Phlox creates a fast-aging clone of Trip in order to generate the neural tissue necessary to save the engineer. Unfortunately, the operation will kill the clone and — worse yet — the nature of the cloning process means the copy of Trip will have all of Trip’s memories, attachments, skills, and desires. He’s not a mere tissue bank; he’s a person. This episode could easily have devolved into a pandering heartstring-tugger of the first order, but the plot is elevated by Sim’s necessary replacement of Trip while the latter is out of commission. The Enterprise is adrift in a dangerous radiation field and Sim, using his inherited version of Trip’s engineering talents, joins the crew in plotting their escape. As such, he becomes a crewmember in his own right, rather than a mere sickbay-hostage copy of Trip to be disposed of. As with all great moral-trap Trek stories, the resolution comes from the heroic sacrifice of a noble soul laying down for the greater good. Science fiction as meditation on ethics and the human condition, with just enough action to keep it fresh: You can’t get any more Star Trek than that.

Disagree with the rankings, or just want to debate the finer points of Enterprise‘s four-year mission? Hailing frequencies are open in the comments section.

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