On September 8, 1966, the first episode of Star Trek: The Original Series, “The Man Trap,” was broadcast. But that isn’t the only Star Trek series to debut on September 8. Less than a decade later, on Saturday, September 8, 1973, the first episode of Star Trek: The Animated Series, “Beyond the Farthest Star,” was broadcast.

To celebrate the anniversary, Paramount is hosting special viewings of the Star Trek: Lower Decks Season 4 premiere on September 8, 2023. There will also soon be new animated shorts in the style of TAS. In the meantime, Trek Tuesday is here to offer eight essential episodes to celebrate half a century of “Those Animated Scientists.”


Two versions of Spock (Leonard Nimoy) with a sick Sehlat.

The second episode of TAS, “Yesteryear,” shows us a side of Spock (Leonard Nimoy) we’d never seen before. A sequel to several TOS episodes, “Yesteryear” sees Spock enter the Guardian of Forever to restore the timeline. This requires him to travel back to his childhood on Vulcan, where he is involved with an essential event involving his pet sehlat.

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While Spock doesn’t fully resolve his issues with his own humanity until the TOS-era movies, “Yesteryear” is an important point of development for the character. Spock’s sehlat is mentioned in dialogue in the TOS episode “Journey to Babel.” However, the magic of animation allows us to see I-Chaya onscreen. Finally, in the Star Trek: Strange New Worlds episode “Those Old Scientists,” Ensign Beckett Mariner (Tawny Newsome) alludes to these events when she asks Ensign Bradward Boimler (Jack Quaid) whether he asked Spock (Ethan Peck) about his pet sehlat.

“The Survivor”

A shapeshifting Vendorian spy extends a tentacle towards an Enterprise crew member.

Lost lovers, Romulans, and shapeshifters — oh my! In “The Survivor,” the crew of the USS Enterprise encounters them all. This episode features a classic conflict between the Romulans and the Federation. However, it is further complicated by the inclusion of a shapeshifting Vendorian spy.

This TAS episode isn’t the last time Vendorians appear in Star Trek. In the Lower Decks Season 1 episode “Envoys,” Mariner and Boimler have a passing encounter with a Vendorian in a bar on Tulgana IV.

“The Infinite Vulcan”

L: Spock Two (Leonard Nimoy) in Star Trek: The Animated Series. R: Ensigns Jet Manhaver (Marcus Henderson) and Beckett Mariner (Tawny Newsome) on Spock Two's skull.

With animation, you can tell stories that would be impractical via live-action. This is demonstrated by “The Infinite Vulcan,” which features a giant-sized version of Spock named “Spock Two.” A scientist who hopes to use the giant Spock to lead a peacekeeping force transfers Spock’s consciousness into the oversized clone. Fortunately, a giant-sized mind-meld is able to set things right.

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However, the giant Spock does not survive as long as the normal-sized Spock. This is revealed in the Lower Decks Season 2 episode “Kayshon, His Eyes Open.” In this episode, Spock Two’s enormous skeleton can be seen hanging in the collection of Kerner Hauze (Fred Tatasciore). As a special bonus, “Kayshon, His Eyes Open” originally aired on the 100th anniversary of Star Trek creator Gene Roddenberry‘s birth.

“The Magicks of Megas-Tu”

Lucien (James Doohan) in the stockhold in Salem.

In “The Magicks of Megas-Tu,” the crew of the USS Enterprise are put on trial in Salem, Massachusetts. Fortunately, Captain James T. Kirk (William Shatner) has the moral fiber to speak out in defense of the Enterprise‘s new friend, “Lucien” (James Doohan). However, you may know Lucien by another name: Lucifer.

This episode tackles some of the most important themes of Star Trek. This includes the frequency with which our assumptions are wrong and the importance of accepting everyone, even those you’ve been taught are “evil.” Plus, this episode features Spock making a pentagram on the floor of an Enterprise room and using it to cast a magick spell. 

“The Slaver Weapon”

R: Two Kzinti shoot at Nyota Uhura (Nichelle Nichols). R: Ensign Taylor (Fred Tatasciore) of the Cerritos.

The TAS episode “The Slaver Weapon” is excellent in its own right. Centering on an away team comprised of Spock, Nyota Uhura (Nichelle Nichols), and Hikaru Sulu (George Takei), the Enterprise and the rest of the crew don’t appear in this episode at all. This episode features a fascinating artifact: the Statis box. However, “The Slaver Weapon” is especially interesting because it also introduces the alien race known as the Kzinti to the Star Trek universe. The Kzinti were created by episode writer Larry Niven in 1966 and were subsequently integrated into Trek.

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The Kzinti continue to be involved in the expanding world of Star Trek. On Lower Decks, the USS Cerritos crew includes a Kzinti: Ensign Taylor (Tatasciore). So far, his biggest role has been in the Lower Decks Season 2 episode “The Spy Humongous.”


L: Bem (James Doohan). His head is floating. R: Yem (Lennon Parham) looks at a PADD.

In this episode, the crew of the Enterprise is observed by the titular Ari bn Bem (Doohan). Like Spock Two and the Kzinti, Bem is an alien who would be difficult to execute in live action, even with today’s technology. Bem is a Pandronian, a colony creature comprised of three separate (and separatable) parts.

This episode was given a sequel through the Lower Decks Season 2 episode “I, Excretus.” In this episode, the crew of the Cerritos is observed by Shari yn Yem (Lennon Parham). But just like Bem, it turns out Yem has ulterior motives.

“The Practical Joker”

Nyota Uhura (Nichelle Nichols), Doctor "Bones" McCoy (DeForest Kelley), and Hikaru Sulu (George Takei) in a simulated hole in the rec room.

What if… the Enterprise had a mind of its own? In “The Practical Joker,” the ship passes through a cloud that causes it to achieve sentience. The antics that ensue are unforgettable. Just one of many possible examples: the Enterprise sticks a sign that reads “Kirk is a jerk” on the back of Kirk’s uniform.

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However, this episode is especially notable for another reason. It is the first appearance of the Holodeck. Called “The Rec Room” here, this episode is the clear predecessor of the many subsequent holodeck appearances on Star Trek. These range from the Holodeck’s supporting role in Star Trek: The Next Generation‘s pilot, “Encounter at Farpoint,” to its central narrative function in episodes like Star Trek: Prodigy Season 1’s “Ghost in the Machine.”

“The Counter-Clock Incident”

L: Admiral April (James Doohan) on TAS. R: Admiral April (Adrian Holmes) on SNW.

While “The Counter-Clock Incident” was the final episode of TAS, it’s also increasingly important for another reason. This episode fully introduces Admiral Robert April (Doohan). 

Before Pike captained the Enterprise, he was the ship’s First Officer under the command of April. The character has enjoyed a resurgence in interest thanks to his important role on SNW, where he is played by Adrian Holmes.

Every episode of TAS is available for streaming on Paramount+.

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