Advised by the Sphere data, Discovery journeys to a mysterious planet in hopes of finding a cure for Georgiou's deteriorating condition. Said cure turns out to be a Portal Door to the Mirror Universe, making its first return since the series' first season. Meanwhile, back in the Prime Timeline, Stamets and Adira make a stunning breakthrough with the newly acquired data on The Burn.
Tropes in this episode:
- Antagonistic Offspring: Mirror Michael is revealed to be this, having willingly sided with Lorca's coup d'etat as he offered her what she sought: a way out of her mother's shadow.
- Apocalyptic Log: The Kelpien distress signal is 150 years old and still going strong. Tilly also notes that the Kelpien in the video log has obvious radiation burns and likely wouldn't have lasted much longer after that.
- Assassin Outclassin': Georgiou kills Mirror Stamets before he can kill her.
- Be as Unhelpful as Possible: Carl dances around who or even what he is, and doesn't explain how his door will help Georgiou, only that her current condition won't affect her on the other side.
- Blatant Lies: Adira claims to be happy Gray is gone, but Stamets sees right through it.
- Kovich tells Culber about the alternate universe that was created by "the temporal incursion of a Romulan mining ship".
- Admiral Vance brings up Airiam's death when asking Burnham if she'll be willing to abandon Georgiou if it comes to it. Burnham cites her failure to do the deed herself then as the reason why she won't hesitate this time.
- Canon Welding: While J. J. Abrams's "Kelvinverse" has acknowledged its debt to the Prime Timeline, this is the first time the Prime Timeline has been directly affected by — or, for that matter, acknowledged — the Kelvinverse. (It's also the first entry in the franchise, from any continuity, to feature the Prime, Kelvin and Mirror Universes all at once.)
- Continuity Nod:
- The hologram of Yor, a time traveler from the 24th century Kelvin Universe, is wearing the jumpsuit uniform from the early seasons of Star Trek: The Next Generation. Whether or not it's an outright Kelvin-verse variant, or he picked it up as a disguise upon arrival in the prime universe, is unclear.
- Carl is heavily implied to be one of the higher beings that's appeared in Star Trek before.
- Stamets intends to use the Kelpien ship's prefix code to access its internal sensors.
- Cruel Mercy: Once she sees Mirror Michael is unrepentant of her actions against her, Philippa spares her after holding back a decapitating swing of her sword, deciding death was too good for her. She has her sent to an Agonizer.
- Even Evil Has Standards: Georgiou, a Terran, is actually disturbed by Mirror Michael's actions, being left speechless when her daughter tells her she mutilated Kepler 174-d's artists. Shortly after, when Michael tries to kill Mirror Saru, Philippa screams a Big "NO!" and stops her from doing so, retaking her ownership of him. This serves to demonstrate how living in the Prime universe has affected her.
- Evil Is Hammy: Just as in every other Mirror Universe episode in Trek, the main cast chew the scenery with gleeful abandon when portraying their counterparts.
- Fate Worse than Death: Georgiou claims she's giving Mirror Burnham this after refusing to execute her, though it's just as likely she can't bring herself to do it and needs an out.
- Georgiou swings at Burnham with a sword, claiming it will be a death blow, but stops short when Burnham refuses to dodge. When Mirror Burnham readies herself to be executed for treason, Georgiou draws her blade to do the deed, only to stop short once again, though this time she leaves a decent cut before stopping.
- Carl is reading a newspaper called The Star Dispatch, the same one which announced the death of Edith Keeler.
- Freeze-Frame Bonus: The other headlines in Carl's newspaper reference a supernova threatening the Tkon Empire and the disappearance of the U.S.S. Jenolan.
- The Ghost: In the Mirror Universe, Captain Gabriel Lorca is making his move against Georgiou, carrying out a purge of officers who are implied to be loyalists of the Emperor while accusing them of sedition. While we see several officers who we know are loyal to him, including Burnham and Landry, Lorca never personally makes an appearance. This makes sense, as he would be aboard the I.S.S. Buran at this time.
- Guy Liner: Mirror Culber sports this.
- Have You Tried Rebooting?: Adira is frustrated that the algorithm hasn't made progress on decoding the distress call in hours, until Stamets notes that the program wasn't restarted after they installed a new component into the computer terminal.
- I Have My Ways: Book tells Saru that he has sources for information — namely, couriers whose names he can't reveal.
- Intangibility: Georgiou starts experiencing this involuntarily as her condition deteriorates.
- Kick the Son of a Bitch: Once Mirror Michael's plans are exposed and she's sent to the Agonizer, Killy knocks her unconscious by kicking her in the face.
- Laughing Mad: When Mirror Burnham confesses her impending betrayal to Georgiou, she's laughing with her mouth stretched unnaturally wide.
- Macho Masochism: At the party, a group of officers, including Stamets and Culber, are shown trying to outlast each other while holding active Agonizers.
- Mercy Kill: Dr. Kovich explains that Yor was eventually euthanized by the Federation because his condition was causing him indescribable agony and they had no other means of alleviating it.
- Mental Time Travel: When Georgiou passes through Carl's door, she winds up in the body of her past self on the day that Lorca attempted his coup. However, she still possesses the wrist monitor that she was wearing in the present, so whatever Carl did isn't a straight example.
- Mommy's Little Villain: Mirror Burnham is just as twisted, sadistic and evil as the Emperor was before she jumped universes. One of the things she casually mentions is blinding and mutilating a group of artists Georgiou told her about to increase the value of their work since they can't make any more.
- Motive Rant: When Georgiou confronts Mirror Burnham.Georgiou: Confess, and I will spare your life.
Burnham: "Confess and I'll spare your life"? (insane giggling) Who are you? Your weakness grows every day.
Georgiou: Do not confuse growth with weakness. My power is absolute, as you have seen. Now tell me what this is really about. You owe me that.
Burnham: Why, because you "plucked me out of a trash heap"? I was master of that trash heap. And now I'm nothing. I'm a tool. I'm just this reflection of you who can never stand on my own. But Lorca ... he loves me for me. And he honors me ... for me.
Georgiou: I gave you every opportunity. It didn't have to come to this.
Burnham: (mad cackling) Of course it did. You want a confession? Yeah. I planned a coup with Lorca. I betrayed you. I betrayed you. And I'd do it again.
- Narrative Poem: Mirror Stamets recites a ballad about Emperor Georgiou at the christening of the I.S.S. Charon, accompanied by a Cirque du Soleil-style performance.Attend, attend, all foe or friend
A tale for you at journey's end
She planted steel and glory sowed
Our sovereign, Emperor Georgiou!
When Klingon forces, savage, vile
Encircled us with guile and wile
A then unknown, a peasant girl
Did vanquish them and save the world.
Honorable, kind, demure
From Heaven sent, of spirit pure
Her blade was swift, her aim was true
Her enemies were bowed from rue.
Then armies of evil assembled against us.
That child, now a woman, was there to defend us.
Guided by light against forces perverse
She brought peace and love to the whole universe.
Overlord of Vulcan, Dominus of Qo'noS
Regina Andor, such gravis onus.
Slayer of Klingons, Daughter of Rome
Welcome, Georgiou, to your new palace home!
- No-Holds-Barred Beatdown: When Mirror Rhys challenges Mirror Owusekun for her position, she kicks his ass and delivers a serious pounding to his face that only ends when Mirror Burnham yells at them to stop.
- Noodle Incident: Implied, as Vance telling Saru that he shouldn't necessarily sacrifice a crewmember to serve The Needs of the Many suggests that there's a personal story behind this advice.
- No One Gets Left Behind: Admiral Vance cites this principle when explaining to Saru why he should help a member of his crew over The Needs of the Many, because neither Saru's crew nor Saru himself would look at him the same way for allowing one of their own to die.Vance: I never listened to advice when I was green, but take it from an old salt who's made a lot of bad calls in his day. A crew member is drowning. If we let her, then your crew will never look at you, or the Federation the same way again. And you will never look at yourself the same way either.
- Not So Different: Georgiou argues that Mirror Burnham and her Prime self both desire to bend others to their will, Mirror Burnham was just honest about it. As Georgiou is being difficult about getting treatment, Burnham just brushes it off.
- Out-of-Genre Experience: Carl is straight out of one of the goofier Original Series or Next Generation episodes, and sticks out like a dozen sore thumbs in the more serious and grounded world of Discovery. This is deliberate.
- Pet the Dog: Georgiou graciously acknowledges Saru as captain and Tilly as a decent choice for Number One before departing. She also protects Mirror Saru from Mirror Michael's rage, shows knowledge of the Vahar'ai and earns his unconditional love. She also spares Michael once her coup plans with Lorca are exposed.
- Pungeon Master: Carl is full of bad jokes."What do you call a cute portal? A-door-able.
"A clown held a door open for me. It was a nice jester."
- Ragnarök Proofing: The Kelpien ship has been sitting in an unstable nebula for a century and a half, yet still has the power and intact infrastructure to transmit a looping distress call the entire time. Adira is amazed it's still going after so long.
- Reality Warper: Whatever Carl is, he's able to appear out of nowhere, send Georgiou's mind back in time and across universes while also sending a physical object back with her, and is nearly undetectable by sensors.
- Reasonable Authority Figure: Vance again. When Saru points out that the Emerald Chain is acting up again, which would scuttle any detour to save Georgiou, Vance authorizes the mission to save her because he knows from experience that taking care of one's crew comes first. It also provides the useful pretense of dumping an unstable Terran halfway across the galaxy, rather than having her on the ship as a potential wild card.
- The Reveal: The signal coming from the source of the Burn is a looping distress call sent by a Kelpien ship a few years before the Burn. The nebula is home to a dilithium nursery that the vessel and its crew were investigating before their ship was disabled. They called for help, but the ship that responded never arrived.
- Set Right What Once Went Wrong: When Georgiou ends up in her past, she decides to try to bring her Burnham back into the fold, averting her fate in the original timeline. To that end, she stabs Mirror Stamets in the middle of the attempted coup, stopping it in its tracks, before confronting Burnham and having her sent to the Agonizer instead of killing her. In the original mirror universe timeline, Burnham was executed while Stamets had been spared after he betrayed the conspiracy.
- Slasher Smile: Mirror Burnham, in spades. Especially when she goes into her Motive Rant.
- Stranger in a Familiar Land: Georgiou gets hit by this upon returning to her own time in the Mirror Universe; her time in the prime universe has left her with an unexpected appreciation for life and what the future can be.
- Suddenly SHOUTING!: When Mirror Saru brings a glass of wine to Mirror Burnham.Mirror Burnham: Did I call ... for WINE?! (hits the glass out of Saru's hand) DID THE EMPEROR?!
- Temporal Sickness: Georgiou's suffering from a double-whammy: not only are her molecules out of their proper time, but out of their proper universe. Either one on its own is no big deal, but both are causing her body to deteriorate as her molecules try to shift in two directions. This isn't helped by the fact that, nearly a millennium later, the two universes are a lot farther apart than in the 23rd century, exacerbating the effect.
- Think Nothing of It:Book: Look, I want to thank you again for what you did on Kwejian.
Saru: No need for thanks. It is the reason for the Federation's existence.
- Title Drop: "Terra firma!" This gets accompanied by the imperial salute, just like "Long live the Empire!"
- Treachery Is a Special Kind of Evil: Normally averted due to the Terrans' embracing of the Klingon Promotion, but played straight in regards to the Emperor. According to Killy, being caught in a coup attempt against the Terran Emperor is punishable by death, with no exceptions.
- Two Lines, No Waiting: The A plot is Georgiou's adventures in the Mirror Universe, the B plot is Discovery's gang of science nerds trying to decode a signal that's coming from the spot where the Burn started. What's unusual is that the show follows a strict Point of View system: all of the B plot stuff takes place while Georgiou is on this side of the door. Once she goes through to the Mirror Universe, the Prime DISCO crew disappears and the show exclusively depicts her adventures. This continues into the next episode.
- Warrior Heaven: It's implied that Terrans believe in one as Georgiou keeps talking about wanting to die in battle and mentions that anyone she kills will be her servant in the afterlife.
- William Telling: At the party, Mirror Bryce throws a dagger at Mirror Nilsson's head to knock a piece of fruit off of it. Curiously, she's a willing participant.
- You Wouldn't Shoot Me: Burnham allows Georgiou to take a swing at her with a sword, knowing Georgiou won't follow through even though she's threatening to.