The Discovery is caught in a 30-minute time-loop (leading to its repeated destruction) due to Harry Mudd, and Stamets is the only one who realizes this.
Tropes in this episode include:
- All Your Base Are Belong to Us: Mudd hijacks the Discovery's computer early in the time loops, and uses it to control the ship's main functions. He even reprograms it to call him 'Captain Mudd'.
- Arms Dealer: Barron Grimes, Stella's father, has made a killing in this business during the FederationKlingon War.
- Big Damn Kiss: Tyler kisses Burnham in one of the loops after she convinces him of what's happening.
- Breather Episode: The episode is light on the drama when it comes to the war or the overall story arc or darker matters such as Lorca's mental state. The only mention of the war is that, thanks to the Discovery, the tide has turned, and Federation is currently winning.
- Bottle Episode: This episode takes place entirely on the Discovery and involves only one character who isn't wearing a Starfleet uniform (three if we count Stella and her father at the end).
- Brick Joke: Early on, Tilly mentions how she used to be into military guys but now has a thing for musicians. To get her out of his hair in a later loop, Stamets points out a random guy and says he's in a band.
- The Bus Came Back: Harry Mudd is back, after being left by Lorca on the Klingon prison ship.
- Call-Forward: Harry Mudd is said to have used his "Groundhog Day" Loop technology to rob a bank on Betazed. The Betazoids wouldn't be formally introduced until Star Trek: The Next Generation.
- Can't Kill You, Still Need You: Invoked by Burnham. When Stamets gives himself up to stop Mudd from killing any more people, Burnham reveals herself to be T'Kuvma's murderer so he'll see her as valuable, then kills herself with one of the dark matter pellets he stole from Lorca's lab. This forces Mudd to reset the loop, only now she's told Stamets exactly what to do to con Mudd into ending it while still thinking he's won.
- Captain's Log:
- Burnham records a log reflecting on how much she's learned on Discovery, accompanied by a Hard-Work Montage.
- "Captain Mudd" records a log entry of his own.
- Cassandra Truth: Stamets tries desperately to get someone to believe him regarding the time loop. He finally, after multiple attempts, convinces Burnham.
- Continuity Nod:
- Betazed is mentioned as a planet where Mudd robbed a bank using his "Groundhog Day" Loop technology.
- A phaser set to stun can still kill a humanoid, if it's to the head at point-blank range.
- The nasty effects of the dark matter pellets are reminiscent of the Varon-T pistol from "The Most Toys", as well as the Klingon disruptors in Star Trek III: The Search for Spock.
- For that matter, the unidentified disruptor that Mudd "tries out" on Lorca for his 54th kill also takes a lengthy time to disintegrate the target, much like the Varon-T did.
- Cruel and Unusual Death: Mudd subjects Lorca and the crew to several of them, including vaporizing them with various weapons, using 'dark matter pellets' he stole from Lorca's lab to tear them apart from the inside out, and even beaming the captain into space and watching him suffocate on the viewscreen.
- Cruel Mercy: Despite his admitted attempt to try and steal the ship to sell to the Klingons and the way he repeatedly murdered the crew, Mudd is allowed to go away with his "beloved" Stella, and having all his prior debts wiped out by his father-in-law, who bought them all so that Harry now owes him. And said father-in-law will make sure Harry never leaves Stella's side. They also seem to not care that Mudd now knows almost everything about the Discovery and the spore drive—information he could still sell to the Klingons.
- Death Montage: Mudd's various killings of Lorca are shown in a montage. Shot, shot again, beamed into space, etc.
- Debt Detester: Grimes doesn't want to be in debt to Starfleet and immediately asks how he can repay them. Tyler's answer is simple — keep Mudd on a tight leash.
- Disproportionate Retribution: Lorca left Mudd behind in a Klingon prison for betraying him and Tyler. Mudd's response is to attempt to steal Discovery, sell it to the Klingons along with its crew, and cause the Federation to lose the war, screwing over billions more in the process. In the middle of that he takes some time to kill Lorca in numerous and increasingly painful ways.
- Due to the Dead: At the party, Tyler makes a speech honoring those who've died in the war.Tyler: Everyone, hey. We're all lucky to be here tonight, surrounded by our brothers and sisters-in-arms. Laughing. Dancing. But let's not forget the sacrifices that have been made by those who still serve alongside us...
Everyone: Here, here!
Tyler: ...and by those who have given their lives for us so we can continue the fight. To the 10,000 souls who are gone, but will never be forgotten.
- Everybody Lives: Despite the many times main characters get killed off during the time loops, by the final iteration, the Discovery crew manages to find a way to thwart Mudd and get him caught without violence. On the other hand, by the end, Mudd has gone through enough In-Universe Catharsis that he doesn't really care to harm anyone unnecessarily.
- Fatal Flaw: Burnham and the crew exploit Mudd's greed to get him to reset one last time, and then play to his ego to convince him he's won.
- Failed a Spot Check: Although Mudd's shown easily avoiding crewmembers whom he knows will come through a door or down a hall because they do so in every loop, he doesn't seem to note that that Burnham, Tyler, and Stamets eventually start showing up in different locations indicating not everything is staying the same. He only clues in when Stamets specifically makes it clear he's retaining memory of the time loops.
- Faux Horrific: In the opening, Burnham recounts how she's starting to fit in on Discovery. However, she dreads what's happening today: a party.
- Finish Dialogue in Unison: A sign of how often Stamets has been through the loop and heard the same dialogue over and over again.Stamets: Burnham, don't talk. Just listen. The ship is in danger. We are caught in a temporal loop. We are repeating the same 30 odd minutes over and over again. The ship can be destroyed. We can be killed. But as long as the 30 minute window doesn't expire, everything starts over. And every second you doubt me brings us all closer to death. Do you understand?
Burnham: Okay. I think we need to get you to Sickbay. I think these might be side effects...
Stamets and Burnham: ...of exposure to alien DNA. It's possible we haven't taken into consideration the cognitive variances...
Stamets: Yes, yes, yes. Please, stop talking. Come with me. I'll explain everything.
- Funny Background Event: Burnham, Tyler, and Stamets have various "You Have GOT to Be Kidding Me!" looks on their faces when Mudd attempts to bullshit his way out of trouble with Stella.
- "Groundhog Day" Loop: The ship is caught in a thirty-odd-minute repeating loop, though it is only Stamets and Mudd who actually experience the loop. In order to break the loop, Mudd has to let the 30 minutes expire, at which point the device he was regulating it with vanishes.
- Hard-Work Montage: The final iteration of the time loop, with the crew preparing to defeat Mudd.
- Heroic Suicide: Burnham kills herself in order to force Mudd to reset the loop, since she's too valuable to the Klingons to let die.
- Horrible Judge of Character: Stella actually seems to genuinely love Mudd. Poor woman.
- Horror Doesn't Settle for Simple Tuesday: The party is implied to be a New Year's Eve bash. The rolling over of the calendar plays into the time-travel theme of the episode.
- Insult Backfire:Burnham: You are mad.
Mudd: No, I'm Mudd.
- In-Universe Catharsis: Mudd is implied to have killed Lorca so many times that he no longer hates him and is actually quite civil in the last loop (albeit still a jerkass).
- Karma Houdini: Despite killing many of the Discovery crew repeatedly through all the time loops, Mudd's punishment amounts to spending the rest of his life with a wife who clearly loves and understands him. Even though all of the deaths at his hands were reset, it's clear that Mudd is still a dangerous sociopath who attempted grand theft of an entire starship, not to mention terrorism against the Federation. Considering he should have spent his remaining days in prison just for killing Lorca, Mudd gets off lightly. Although admittedly he's now in the absolute power of his father-in-law, who's none too fond of him, and we know that this marriage will go rather sour within the next ten years or so. And Mudd has no real hope of selling any useful information to the Klingons, since Mudd never got to the point of figuring out the spore drive's inner workings, and the Klingons have already seen its capabilities in action from the receiving end.
- Lampshade Hanging: Courtesy of Stamets."As days go, this is a weird one."
- Leave the Two Lovebirds Alone: Tilly's intention when she leaves Tyler and Burnham at the party.Tyler: Your friend's subtle.
Burnham: Inappropriately so.
- Mad Oracle: Stamets plays this role. The "oracle" part comes from his Ripple Effect-Proof Memory; the "mad" part from his generally stoned demeanor as the result of plugging himself into the spore drive.
- Mid-Season Upgrade: Two episodes after Stamets gave himself tardigrade DNA, he and Culber come up with forearm implants to make the interface easier. The next episode will reveal that the gizmo in the spore cube has also been modified to facilitate the interface.
- Mundane Solution: Instead of some big, gimmicky way of beating Mudd, the crew utilize two non-critical systems (the library computer and the captain's chair) to trick him into calling Stella and her father.
- Mythology Gag:
- Near-Villain Victory: For a short time, Mudd does seize control of Discovery. But once he finds out who Burnham is (and after she kills herself), his greedy nature causes him to reset the loop again so that he can have both the ship and her as a prize for the Klingons.
- Noodle Incident: Mudd is pretty vague on the details of how he escaped from that Klingon prison ship.
- Not a Date: Burnham claims that the time she's spent with Tyler isn't dating, despite Tilly's assertions otherwise.
- Oh, Crap!: Mudd realizing that he's been played and that he inadvertently summoned his fiancee and her father.
- Our Dark Matter Is Mysterious: Harry Mudd uses capsules of dark matter as weapons against the Discovery crew. They're shown as little purple-glowing balls that disintegrate people they hit.
- Power Perversion Potential: Once Burnham convinces Tyler that the ship is trapped in a time loop, he kisses her since he figures it won't matter anyway.
- Progressively Prettier: Mudd's wife Stella appears about half his age in this version, as well as far less of a harridan. It kind of dilutes the effect that this is supposed to be a Fate Worse than Death. On the other hand, the future android version of Stella was Mudd's vision of her Informed Flaws made incarnate.
- Red Shirt: "Random Communications Officer man", as Mudd puts it.
- The Reveal: Despite his claims in his previous appearance, it turns out Mudd never loved Stella at all; he was only interested in getting his hands on her dowry.
- Ripple Effect-Proof Memory: Stamets is the only one aware of the time loop as a consequence of his self-experimentation, while Mudd remembers due to being responsible for it. On the other hand, Stamets admits it's getting harder to keep things straight throughout all the loop cycles. Interestingly, the viewpoint characters are still Burnham and Tyler, with Stamets only sometimes appearing when he's managed to find them in the current loop (though in the later iterations, they are informed so quickly of what's happening that they might as well have the memory themselves).
- Save Scumming: Mudd uses his "Groundhog Day" Loop technology to memorize all of the ins and outs of Discovery, learning more with each loop, so he can hijack control of the ship. He also used it to rob a supposedly impregnable bank on Betazed (which is no mean feat, considering that Betazoids are mind-readers).
- Silent Whisper: When Stamets asks Burnham to tell him a secret to prove the time loop the next time, she whispers something in his ear, to which he says, "I'm sorry." In the next loop he finds her at the party and blurts out, "You've never been in love."
- Shipper on Deck: Tilly is trying to get Burnham and Tyler together. Stamets is also pushy about their relationship before the loops start, in his own way. He actually does end up helping them get together, but only because he needs Burnham to question Tyler about Mudd and had no luck doing that himself.
- Sickeningly Sweethearts: Stella and Mudd. Well, Stella at least; Mudd looks like he'd rather be anywhere else.
- Something Only They Would Say: Stamets eventually gets Burnham to tell him something no one else knows so he can use it to convince her about what's going on faster in subsequent loops.
- Space Whale: The Gormagander, an endangered spacefaring creature that Burnham even simplifies as a "space whale." Standard Starfleet procedure upon finding one is to transfer it to a Federation conservation area and breeding program.
- Thrown Out the Airlock: Mudd kills Lorca in one loop by having the computer beam him into space.
- Time Skip: The episode shows the first iteration, in which Mudd doesn't even make it out of the cargo bay before resetting time, then skips the next few dozen (except in flashback during Lorca's Death Montage) since they presumably consist of Mudd getting repeatedly caught until he learns the ship's patterns.
- Time-Travel Tense Trouble: Wouldn't be a time-travel episode without it.Mudd: (to Lorca) So I will see you later...or, rather, earlier.
- Trojan Horse: Mudd hides his ship inside the Gormagander so Discovery will bring it aboard.
- Trust Password: Burnham tells Stamets that she's never been in love when he requests a secret that will make her trust him on subsequent loops.
- Verbal Backspace: Mudd has one while trying to get out of trouble with Stella.Mudd: Well, you know how much you meant to me. (off Stella's look) Mean.
- Victory Is Boring: Mudd eventually repeats the loop so many times he gets tired of gloating and becomes much more matter-of-fact. There's so many repeats that despite being shown taking great delight in finding new ways to kill Lorca due to Mudd's utter hatred of him, by the end he's civil toward Lorca and quite willing to let him live, merely beaming him to the brig.
- What Happened to the Mouse?: The previous episode ended on a Cliffhanger with Admiral Cornwall captured by the Klingons. Given the serialized nature of the show thus far, it's a bit jarring for the format to switch to a somewhat less serious Bottle Episode without even an acknowledgement of her situation. Subverted in that the next episode, "Si Vis Pacem, Para Bellum," does include Cornwell and her continued predicament.
- You Have to Believe Me!: Stamets says this to Burnham, as he needs her help to save the ship and she can't remember the loops. Classically, she explains to him why he's not making any sense and he speaks the entire monologue along. Since the loop is almost up he then asks for an actual Trust Password for future loops. Before that, though, he gets her attention by mentioning the gormagander before Discovery encounters it.