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The Lower Decks Connection: Personality and Body Swaps

One of the strangest Starfleet anomalies is how the crew can shift personalities at the drop of a sci-fi hat.

Illustrated banner for Star Trek personality and body swaps

Welcome back to The Lower Decks Connection, where we curate a watch list of legacy Star Trek episodes based around a plot from the latest episode from Star Trek: Lower Decks! This week, Rutherford really went through a tough time. His implant glitched and suddenly he regressed to his pre-implant self; this came as a surprise to everyone around him, as pre-implant Rutherford is more of a devil-may-care flyboy than a chipper, upbeat ensign.

Ultimately, Rutherford is restored to his normal self after a detour through his subconscious. While he still has questions about how exactly he got his implant, the day is saved. At least for now…

This isn’t the first time that a Starfleet officer has undergone a sudden personality change. Throughout Star Trek history, crews have suddenly faced off against one of their own who’s personality has radically shifted, usually for the worse. Read on for your weekly watch list!

Captain Kirk talks to Sulu, who is holding an alien. The alien is a dog in a costume with a horn on its head.

Even with an engineer as excellent as Scotty, transporter mishaps can still happen. Sometimes, it results in splitting a person into their good and evil selves, which happens to Captain Kirk on one occasion. Kirk’s good self is indecisive, while his evil self is far too aggressive; the captain needs both sides of himself to be the kind of captain his crew needs. Plus, this episode features an amazing alien – a dog with a fluffy costume and a horn on its head. It’s a classic Trek episode.

When the Enterprise arrives at the colony Omicron Ceti III, which has been exposed to radiation and the inhabitants presumed dead, they find the colonists happy and blissful. Soon, due to some strange flowers, this happiness begins to spread to the crew itself, costing them their ambition and discipline in exchange for pure happiness. Spock becomes infected, and a smiling Spock is surely a sign that something is afoot. After all, the science officer is not exactly known for being the most joyful of Vulcans.

Data sits at his post on the bridge.

Data has a new personality uploaded to him in this Season 2 episode. While trying to assist in preserving the research of a dying scientist, Dr. Ira Graves, Data becomes close to to the man who claims he taught Dr. Soong everything he knows. When Graves dies, Data begins to act strangely, leading Picard to investigate. It is revealed that Graves transferred his mind into Data in an attempt to cheat death. The episode tackles philosophical issues of death and immortality as Graves' personality threatens to become the dominant personality in Data's mind.

Troi, Data, and O'Brien, who have been possessed by aliens, hold the crew at phaser point.

During a routine mission, Troi, Data, and O’Brien become infected by three lights that turn out to be the spirits of prisoners whose transport crashed on a moon years before. As many have tried, they try to take over the Enterprise so they can return to their home planet. It’s only due to the quick thinking of Picard and his crew that they outwit the beings and manage to beam them back to the moon below.

Dr. Bashir, possessed by an alien, talks to the crew via the DS9 ops viewscreen.

On their way back from a mission, Kira and Bashir run into a damaged ship in charge of transporting a dangerous criminal named Rao. Rao “dies” during the rescue, but it turns out he transferred his consciousness into Bashir when the doctor tries to resuscitate him. Controlling Bashir’s body, Rao tries to escape with a freighter full of deuridium. Luckily, the crew is able to save Bashir and free him from Rao’s control, even as Rao uses his newfound body as a hostage. With consciousness jumping and a moral dilemma over to save one versus many, it’s a classic set up for a Star Trek episode.

Julian Bashir Bond

Of course a holodeck episode had to make the list! Bashir is trying to enjoy his spy-themed holoprogram, despite Garak’s intrusion, when the rest of the crew’s transport signatures are stored in the holodeck to prevent them from disappearing. As a result, Sisko, Kira, Dax, O’Brien, and Worf become characters in Bashir’s program. It’s up to Bashir to prevent any of the crew from being harmed, as well as survive himself. The actors do a stellar job giving performances as characters who are the polar opposite of their usual roles.

B'Elanna Torres, without her Klingon features, looks upset.

B’Elanna Torres is split into two versions of herself – her human self and her Klingon self – after an encounter with the Vidiians. As Torres has struggled with her conflicting sides of her character, this episode gives them a chance to play out in front of our eyes, ending with her human self admitting that she feels incomplete without her Klingon half. It’s a powerful character study that helped Torres become even more of a beloved member of the Voyager crew.

The Doctor holds a phaser.

The EMH is activated during an emergency, but he soon discovers he can bleed and feel pain. Coming to the mistaken realization that he’s actually Dr. Zimmerman, his programmer, the EMH then believes he’s trapped in a simulation, one he must end so he can move on with his life. It takes some quick thinking from Chakotay to convince the EMH that he is indeed a hologram, and to stop him from accidentally destroying himself. As the EMH grappled with questions of personhood throughout the show’s run, this was a perfect way to grow his character.

T'Pol is in close up. She looks pale and visibly ill.

This episode was featured on a previous Lower Decks Connection list centering on the crew seeing things that aren’t there, but it’s notable for how T’Pol’s personality shifts as well. When the crew goes after a Vulcan ship that sent out a distress call, they discover the crew behaving in a decidedly un-Vulcan like way. T’Pol herself starts to succumb, accusing Archer of wanting to kill all Vulcans. Ultimately, the source of the change is discovered and T’Pol is cured, but the rest of the Vulcan crew is not so lucky. Let us know if we missed your favorite episode on social!