It’s science inside and out of Starfleet in a Star Trek: Lower Decks episode that covers both outpost scientists and the beginning of Science Officer training for Ensign D’Vana Tendi (Noël Wells). The third episode of Lower Decks season 3, “Mining the Mind’s Mine,” was written by Brian D. Bradley and directed by Fill Marc Sagadraca.

RELATED: Read our recap of Star Trek: Lower Decks “The Least Dangerous Game.”

On the rocky planet Jengus IV, a Federation scientist named Tony scans a glowing green orb with a tricorder. Behind him, a scantily-clad apparition of his seventh grade geology teacher appears. She has knowledge of the “racecar novel” he’s writing. Tony proudly explains that he’s self-inserted himself. 

Tony approaches the apparition. When they touch hands, he’s transformed into stone. From a ledge above, a silicate creature with a glowing staff watches with approval.

Lower Decks: “Mining the Mind’s Mine”

Later, the Cerritos orbits Jengus IV. Captain Carol Freeman (Dawnn Lewis) records the Captain’s Log for stardate 58256.2. She explains that the planet was believed to be uninhabited before the Scrubble began turning Federation scientists into statues. 

Captain Murakami of the USS Hood has brokered tentative peace. Now, the Cerritos and fellow California Class ship the Carlsbad are left to clean up the mess. The Carlsbad has a blue stripe, indicating a focus on science. By contrast the Cerritos has a yellow stripe, indicating it has an engineering focus.

RELATED: Mike McMahan Dishes on Star Trek: Lower Decks and Cali-Class Cuisine.

In a ready room aboard the Cerritos, First Officer Commander Jack Ransom (Jerry O’Connell) is ranting about outpost scientists. Ensign Beckett Mariner (Tawny Newsome) is reluctantly listening. Meanwhile, Lt. Commander Steve Stevens (Ben Rodgers) listens raptly.

Ransom gets to the mission parameters. The Cerritos will be removing the green glowing orbs from the cold open. He explains they read your thoughts, bring your fantasies to life, then turn you to stone. Further, Ransom insists the Cerritos away team make a good impression on the Carlsbad crew. Cali Class gets “real gossipy.” Ransom tells Mariner to follow orders issues by Stevens as if they were his own.

Time to Do Science

In the hallway, Ensigns Mariner, Bradward Boimler (Jack Quaid) and Samanthan Rutherford (Eugene Cordero) encounter Tendi. She explains she’d like to join them on Jengus IV. However, she’s starting senior science officer training. 

Tawny Newsome as Ensign Beckett Mariner, and Noel Wells as Ensign Tendi. They chat in the halls of the Cerritos as Tendi clutches a PADD.

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Tendi enters the Cerritos bar and is hailed by Counselor Migleemo (Paul F. Tompkins). He reveals that he has been assigned as her mentor. 

On Jengus, the Cerritos away team beams in and is immediately greeted by Ensign Kearns (Kari Wahlgren). Kearns explains she and two other Carlsbad ensigns will provide assistance. Stevens orders the Carlsbad team to dismantle and relocate the outpost equipment. Meanwhile, the Cerritos team will collect and contain the fantasy rocks.

Bradward asks what they should do if their fantasies appear. Stevens tells them to just ignore the fantasies until they go away.

Mariner introduces the Cerritos team to the Carlsbad team. The Carlsbad team says they’ve heard how they do things on the Cerritos, but they’re not here to mess around. Rutherford says they were acting like the Cerritos was a joke, wondering about their reputation.

In the Cerritos bar, Migleemo admits he’s never trained a science officer. In fact, he didn’t know they even did this. They’ll be learning together. Migleemo begins skimming the science officer training manual. Tendi tries to test out of the mentorship. However, Migleemo says the training is “about learning to be the voice of science” (according to the manual).

Migleemo assigns Tendi to work with Captain Freeman. It’s a sink or swim situation, and Migleemo confirms that Freeman will probably get mad.

Fantasy Planet

Rutherford, Boimler, and Mariner clear the glowing green orbs. 

Geordi LaForge (LeVar Burton) and Leah Brahms (Susan Gibney) on Star Trek: The Next Generation.

Samanthan is tempted by a vision of Leah Brahms (Susan Gibney). Brahms is the Galaxy Class starship designer who appeared in multiple episodes of Star Trek: The Next Generation.

Beckett is fixated on the reputation they have with the Carlsbad ensigns. She claims Cali Class ships are all practically the same. Rutherford and Bradward counter with a laundry list of notable shenanigans undertaken by the Cerritos. Mariner says they’ll kick their asses Cerritos style, but the Carlsbad ensigns are kicking butt. The beta shifters are motivated to up the ante with the glowing orbs.

Samanthan continues to be tempted by Brahms. Beckett and Boimler laugh but are subjected to their own fantasies. Bradward sees a Starfleet Admiral. Mariner is tempted by a bikini babe version of Jen the Andorian (Lauren Lapkus) who is really into labels.

On the Cerritos, Tendi enters the meeting room. There’s a spread of snacks including an Enterprise cheese board and Starfleet insignia-shaped crackers. Freeman, Ransom, and Kayshon stand on one side of the table and gossip. Freeman approaches Captain Maier (Baron Vaughn) but there’s a clear generational divide.

Shax (Fred Tatasciore) enters with Holden the outpost scientist and a Scrubble. They’re arguing with one another. Freeman wrestles their attention and says they have the treaty agreements on hand. The Scrubble offers a stone statue as a token of appreciation.

Soon, Maier and Freeman are arguing with one another over who will keep the stone token. Both heavily emphasize the other’s age.

Fantasy Basketball

Meanwhile, the beta shifters ignore their fantasies as they get the orbs contained. Mariner is openly competitive with the Carlsbad Lower Deckers. Stevens urges caution “dunking” the fantasy orbs like “basketballs.” But Beckett emphasizes that they want to make Ransom look good in front of the Carlsbad crew.

Goaded by imaginary insults to Ransom, Stevens knocks over the vat of orbs. Many break, releasing a green gas. Stevens postulates that this will just create a “really big” fantasy. 

Tawny Newsome as Ensign Beckett Mariner, and Ben Rodgers as Steve Stevens in the Lower Decks episode "Mining the Mind's Mines." They look on with concern as the fantasy orbs shatter and green gas is released.

Big ham sandwich incoming? From Lower Decks s3e3, “Mining the Mind’s Mines.”

Instead, Kukulkan from the Star Trek: The Animated Series episode “How Sharper Than a Serpent’s Tooth” appears. He chases Stevens down and turns him to stone. 

RELATED: Star Trek: Lower Decks season 3 – The Search for Speculation.

The Lower Deckers quickly surmise that the broken rocks aren’t reading their fantasies, they’re reading their nightmares. Soon they’re being chased by a variety of nightmares. These include Borg snakes, Klingon clowns with Batleths for arms, and a giant monstrous raisin. Bikini Jen is attacked by a Starfleet uniform-clad werewolf Jen who is obsessed with commitment.

The nightmares chase the Lower Deckers into a cave. An intentional cave-in seals them in. Comms are blocked. Mariner accepts responsibility for making everyone rush. Boimler admits that it was clear the Cerritos has a bad reputation and they wanted to impress the Carlsbad crew.

The Lower Deckers travel deeper into the cave in "Mining the Mind's Mine." Kari Wahlgren as Ensign Kearns, Paul F. Tompkins as Ensign Young, Carl Tart as Ensign Cor'Dee, Eugene Cordero as Ensign Rutherford, Tawny Newsome as Ensign Beckett Mariner, and Jack Quaid as Ensign Brad Boimler.

The Lower Deckers dig deeper.

Kearns admits they were rushing because they wanted to impress the Cerritos crew. The Carlsbad crew reveals the other Cali Class ships actually perceive the Cerritos to be really cool.

In the negotiation room, Maier and Freeman are still arguing over the rock. Freeman orders Tendi to scan it and tell Maier it’s “just a rock.” But Tendi learns it has an anomalous molecular composition. Freeman shuts her down. The two Captains continue to argue.

Nightmare Basketball

In the Jengus cave, the Cali Class ensigns bond. Kearns admits that everyone looks up to the Cerritos and they just wanted to impress the beta shifters.

They’re interrupted by Rutherford’s nightmare Borg snake. After it coughs up a basketball, they successfully repel it with phasers. They question why it coughed up a basketball, which is unrelated to either Samanthan’s fantasies or nightmares. However, Rutherford overheard Stevens mentioning basketball earlier.

Kearns wonders why the stones would access that part of the brain. Bradward observes there are other inexplicable elements to the “nightmares” outside. Beckett realizes the werewolf Jen is wearing the type of hat she overheard another crewmember talking about a few days earlier. The orbs are probing more than they thought.

The Lower Deckers use tricorders to trace a signal coming from further back in the cave. Rutherford’s implant provides light.

Noel Wells as Ensign Tendi seeks the advice of Gillian Vigma as Doctor T'Ana, who is helping a crew member with an alien foot parasite. From the Lower Decks episode "Mining the Mind's Mine."

Sometimes you gotta mess things up.

In the Cerritos sick bay, D’Vana seeks advice from Doctor T’Ana (Gillian Vigman). T’Ana encourages Tendi and tells her that sometimes she’ll need to make a mess of things in order to fix them. She’ll have to risk screwing things up in order to reach her goal of being a great bridge officer.

In the cave, the Lower Deckers find a door. Behind it is the receiver for the fantasy rocks. They discover that the orbs have been scanning every aspect of their brains. Everything from personal life details to sensitive Starfleet passwords and intel is collected. 

Furthermore, the equipment surrounding the set-up is all Federation tech. The outpost scientists must have installed it. The Lower Deckers conclude that the scientists must be working with the Scrubble. But since the cave blocks comms, they’ll have to fight their way out in order to inform their ships.

Beneath the Surface, Lower Decks

In the conference room, Freeman and Maier continue to argue over the stone. Ransom orders Shax to phaser the rock. The Scrubble protests that it is a sacred gift. He says he won’t sign the treaty unless someone accepts it. Shax is having flashbacks.

The conference room debacle from Lower Decks: "Mining the Mind's Mines"! Featuring Baron Vaughn as Captain Maier, Fred Tatasciore as Lieutenant Shaxs, Dawnn Lewis as Captain Carol Freeman, and Noel Wells as Ensign Tendi.

No, YOU take the rock! From Lower Decks s3e3, “Mining the Mind’s Mines.”

That’s when Mariner and Kearns enter and try to explain what they’ve learned. But everyone’s yelling. Tendi picks up the stone and shatters it, silencing everyone.

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Freeman asks if she’s lost her mind. D’Vana points to a Federation tech inside the stone. The anomalous reading was an internal power source. Beckett backs her up and reveals the Scrubble and the scientist have been working together. They have co-devised a system that reads minds and records the information using Federation tech.

Freeman and Maier realize they wanted to put the stone gift in a Captain’s quarters to steal secrets. Freeman says they’re finally ready to start the meeting.

Supplemental Log

In a supplemental Captain’s log, Freeman summarizes that the animosity between the Scrubble and the scientists was a manufactured deception. It was all subterfuge to distract from a plan to sell Starfleet secrets on the black market. 

In the Cerritos bar, the combined Cali Class crews celebrate uncovering the truth. 

Stevens has been de-stoned and has both arms in a cast. His dialogue suggests that while brain dead, he witnessed a koala sitting on a “Black M – “ (presumably Black Mountain). Then he spills cinnamon Schnapps in his eye.

Migleemo takes credit for being Tendi’s mentor. But D’Vana clearly views T’Ana (who is flirting with Shax) as her guide. Captains Maier and Freeman each agree to keep a deactivated fragment of the stone to commemorate the mission.

Elsewhere, the Carlsbad ensigns share a table with the beta shifters. Kearns says that they lived up to their reputations. Except Boimler. Ensign Cor’Dee (Carl Tart) says he’s described as “a tiny comedic robot that is always getting into trouble.” Everyone laughs as Bradward insists they inform everyone he’s people.

Read all of our Star Trek: Lower Decks recaps, here. 

New episodes of Star Trek: Lower Decks are available for streaming on Paramount Plus on Thursdays.

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