Star Trek celebrates 50 years of shaping the pop culture landscape this year, culminating with the release of Star Trek Beyond, the third film in the divisive reboot series, and production on a new television series overseen by alum Bryan Fuller. With more Trek on the way, what better way to prepare and to celebrate the forthcoming new entries than by revisiting the old?

After 50 years, there's no shortage of Star Trek, both good and bad, to go around. The original series and its various spinoffs comprise literally hundreds of hours of viewing, as do the ten feature films. Of course, not every outing demands revisiting. Trekkies will note that,for as incredible a story as Star Trek can tell, the show and films have also plumbed the depths of bad storytelling. So were to begin, and how to best experience Trek?

That's why we're here.

Find here, in no particular order, fifteen of the most popular and best written outings for the Starship Enterprise and her spin-offs. Note that you'll not find either of the J.J. Abrams reboot films here - because you've probably seen them already. The entries here provide an overview of the Trek universe and its history, as well as the dynamics the series has explored.

Here are 15 Episodes (and Movies) To Watch Before Beyond.

15. JOURNEY TO BABEL (TOS)

Perhaps the first "mythology" episode of Trek ever, "Journey To Babel" explores Vulcan culture against the backdrop of a Starfleet conference. The plot features an intergalactic whodunit, though the big draw is the introduction of Spock's parents, Sarek and Amanda Grayson.

Sarek, as played by the late Mark Lenard, becomes a recurring presence in both the films and subsequent series, and his contentious relationship with his son provides loads of insight into Spock's inner conflict. Writer D.C. Fontana makes her first of numerous solo outings writing the show with great results; her contributions would follow the show to present day. Quite simply, it's Trek at its best.

14. The TROUBLE WITH TRIBBLES (TOS)

Even non-Trek fans likely have a passing familiarity with Tribbles, the tiny fuzzballs that do little more than eat and mate. Perhaps the most popular episode of the original series, sci-fi legend David Gerrold makes his Trek debut penning the teleplay.

With "The Trouble With Tribbles," Star Trek also makes its first detour into comedy with great results, as well as the more ensemble cast format that continues to persist in every subsequent incarnation of the show. A perfect blend of action, mystery and hilarity, “The Trouble With Tribbles” remains a jewel in the crown of the franchise.

13. THE BEST OF BOTH WORLDS (TNG)

Star Trek’s many alien races have become pop culture touchstones, and no species of The Next Generation origins looms larger than the Borg. Moreso than any other of their numerous appearances in Trek canon (or non-canon, for that matter) , their outing here testifies to their terrifying power, and forever changed the trajectory of the show.

“The Best of Both Worlds” sees Patrick Stewart’s Capt. Picard abducted and assimilated by the Borg, as the Enterprise crew fights to save their leader. Full of real ethical drama and rousing action, it ranks as one of the best Trek stories ever.

12. YESTERDAY'S ENTERPRISE (TNG)

As quintessential sci-fi, Star Trek has explored just about every aspect of the genre imaginable. Thus, the franchise is no stranger to time travel stories, though few use the concept better than “Yesterday’s Enterprise.”

The episode introduces an alternate timeline where the Federation and Klingon Empire engage in a war of attrition. The occasion affords a chance to see a fully militarized Starfleet…and the return of popular character Tasha Yar. Though a one-off episode, “Yesterday’s Enterprise” has radical effects on the rest of the Trek series. It also might just be the best episode of The Next Generation.

11. MEASURE OF A MAN (TNG)

Season 2 of The Next Generation has a bad rap among viewers—and with good reason. The second season saw the departure of Beverly Crusher (Gates McFadden) from the show, not to mention a series of episodes troubled by striking writers and production turmoil.*

One bright spot almost redeems the numerous missteps of the second season: “Measure of a Man.” Star Trek is always at its best when confronting real moral and ethical questions, and here, Picard and Riker (Johnathan Frakes) face off over the nature of the android Data (Brent Spiner). All three actors deliver some of their best work, and rarely has the writing for Star Trek reached such a thoughtful and emotional high.

*For more information on the troubled production of the first seasons of  The Next Generation, check out William Shatner’s excellent documentary Chaos on the Bridge. Chock full of alumni from all iterations of the franchise—including heavy hitters like John Pike, Rick Berman and Jeffery Katzenberg—it offers a candid glimpse into the world of television production, Star Trek fandom, and an iconoclastic look at the persona of series creator Gene Roddenberry.

10. IN THE PALE MOONLIGHT (DS9)

Deep Space Nine alienated and divided a good portion of Star Trek fandom by focusing on a single galactic location—the titular space station—rather than on exploring the universe. The premise does, however, afford Trek the opportunity to explore ethical dilemmas in a new way.

The crux of the series is the Dominion War, a conflict which saw new levels of violence introduced to the franchise, and disrupted the socialist utopia of the Federation. “In the Pale Moonlight” raises the possibility of the Federation losing the war to their brutal rivals, and explores the question of the end justifying the means. The plot is best experienced with little introduction, so we’ll leave it for you to watch. Prepare to shiver at some of the twists!

9. MORE TRIBBLES, MORE TROUBLES (ANI)

Trekkies often overlook The Animated Series as a cheap curio—a bone to throw to the legions of Star Trek fans following cancellation of the original show, but before the film series revived the concept. Featuring the original cast and many of the original writers, the show is better than its reputation.

Case in point: this sequel to “The Trouble with Tribbles” penned by original scribe David Gerrold. It revisits the troublemaking fuzzballs with the same glee and humor that made the original episode so popular, and should be required viewing for fans of the franchise. Just because it's a cartoon doesn't mean its makers didn't care any less.

8. YESTERYEAR (ANI)

Like “More Troubles, More Tribbles,” “Yesteryear” builds on the series mythology and explores insight into the character of Spock. D.C. Fontana contributes the script, about an elder Spock traveling back in time to save his own life as a child. And like "More Tribbles , More Troubles," "Yesteryear" is an episode of the short-lived Animated Series.

A fine Trek story on its own, “Yesteryear” also takes full advantage of the animated format by introducing plenty of strange environments and creatures, as well as the built-in child audience by exploring young Spock’s relationship with his pet. Sweet, touching, and thoughtful, its great Trek from start to finish.

7. TRIALS AND TRIBBLATIONS (DS9)

Tribbles again? And how!

Deep Space Nine marked the 30th anniversary of Trek by taking full advantage of the series mythos as well as the then-new technology of computer-generated imagery by sending the DS9 crew back to the classic USS Enterprise and the episode “The Trouble With Tribbles.”

Captain Sisko and the crew must stop a time-traveling villain from destroying the Enterprise. The much-touted episode met with rave reviews upon its debut, and earned an Emmy nomination for the script. It’s a joy for fans of the franchise, and a fitting tribute to the older series, proving that Star Trek could move forward without forgetting what came first.

6. SCORPION (VGR)

The fourth live-action Star Trek series, Voyager, got off to a rocky star. Fans complained about a glut of boring characters, stale writing and a lack of familiar alien races. That all changed with this two-part episode, which radically changed the dynamic of the series by introducing its most iconic character—Seven of Nine.

The sultry Borg, as played by Jeri Ryan, became the key character in this two-part story about the Voyager making a pact with the alien menace. The story also introduces Species 8472, an insectoid alien race which threatens to wipe out both the Borg and the Voyager. The episode ushers in a new level of computer special effects to Voyager, and offers heart pounding adventure from start to finish.

5. ENDGAME (VGR)

Few series finales satisfy in the way the penultimate episode of Voyager does; it might just be the best darn episode of the whole show. Tying together series-long story threads and the cultural phenomenon of the Borg, the episode finds Janeway (Kate Mulgrew) facing off against the Borg Queen (Alice Krige, reprising her role from Star Trek First Contact) in a last ditch attempt to return Voyager to Earth.

Mulgrew rises to the occasion, delivering a vigorous performance as both a younger and older version of Janeway, reminding fans why Janeway deserves mention alongside Captain Kirk, and in the pantheon of great Star Trek characters.

4. STAR TREK: THE WRATH OF KHAN

Speaking of series finales, though the original series never had a proper end, director Nicholas Meyer tried to bring Star Trek to a proper conclusion with The Wrath of Khan. With the original cast aging, and the movie franchise stalled, Leonard Nimoy had decided to retire from playing Spock, and The Wrath of Khan would mark a final curtain to the character. Spock would die, and his death would symbolize the end of Trek.

Instead, the movie revitalized the franchise. The story of Captain Kirk’s mid-life crisis and the loss of his best friend continue to inspire audiences, thanks to clever writing by Meyer and performances that feature Shatner and Nimoy at their very best. Ricardo Montelban, as the titular Khan, also delivers a performance of pure contempt and bitterness, becoming one of the screen's all-time great villains.

3. IN A MIRROR, DARKLY (ENT)

Enterprise is the annoying stepchild of the Star Trek franchise: an overproduced, ill-conceived, underwritten snoozefest devoid of the characters and storylines that makes the series great. On the other hand, it does have occasional moments, like this episode. Set in the “mirror universe,” it ties in with both the main Enterprise storyline, and that of the original series, and is probably the best of all the Enterprise episodes.

It probably resonates best with the die-hardest of fans because of its many references to Trek mythology, and for that reason, it remains one of the few episodes of Enterprise worth watching.

2. STAR TREK: THE VOYAGE HOME

If The Wrath of Khan revitalized the Star Trek franchise, the fourth film in the series, The Voyage Home catapulted the cult franchise into the stratosphere, elevating it to a pop culture phenomenon.

The film takes an abrupt turn to comedy with great results, as well as injecting a timely environmental message into the story. Kirk and the Enterprise crew travel back to 1980s San Francisco to procure a pair of humpback whales and save the future. The cast is clearly having fun with the material, and the self-referential wit makes the film priceless to Trek fans, or viewers just wanting a great time at the movies.

1. STAR TREK: THE UNDISCOVERED COUNTRY

The true finale for the original series cast, The Undiscovered Country, sees the Enterprise crew at the end of their careers through the prism of coming galactic peace. Who is Kirk without having the Klingons as rivals? The film mixes a fine balance of humor, adventure and political symbolism to give Kirk and company a great send-off, as well as a meta commentary on the Star Trek series going on without the original cast and crew.

It also features a delicious turn by Oscar winner Christopher Plummer as a Klingon general with a penchant for reciting Shakespeare. Coming the same year the Soviet Union dissolved, and given how much of an influence the Cold War was on the Original Series, it was fitting time for the characters to hang up their Starfleet uniforms.

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Can you think of any other episodes that deserve a looky-loo before Star Trek Beyond comes out? Let us know in the comments!