Discovery Season 5 Episode 5 Easter Eggs Reveal the Fate of a Classic Star Trek Ship

From the Mirror Universe and the ISS Enterprise to a big reveal about the Breen, Discovery season 5 just referenced a a huge swath of the Star Trek timeline.

Star Trek: Discovery Season 5 Episode 5
Photo: John Medland/Paramount+

This Star Trek: Discovery article contains spoilers.

As both a prequel and sequel to various versions of the Star Trek franchise, Star Trek: Discovery often includes unexpected easter eggs and references to the entire saga. The latest episode, “Mirrors,” is no exception, as it brings back a famous Star Trek ship, as well as answers questions about a mysterious alien species, which has been around since the 1990s.

From references to the goatee version of Spock, to some deep-cuts from Deep Space Nine, and even a tribble joke, Discovery’s easter eggs in season 5, episode 5 aren’t messing around. Here are the best references and how these shout-outs solve a few mysteries, while suggesting a possible future development for the next Star Trek show.

“Classic Work on Kellerun”

Early in the episode, Rayner and Burnham talk about which stories are considered classics on the planet Kellerun. Rayner is a member of the Kellerun species, which were established in the DS9 episode “Armageddon Game.” We actually know very little about the Kellerun species, so Discovery is inventing new canon here, rather than referencing anything from previous Trek shows.

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Wormhole and the Burn

The wormhole that Book and Burnham have to enter is unstable, which describes most wormholes featured in Star Trek. But, in this case, it’s suggested that the matter/anti-matter reactions in this wormhole were caused by the Burn.

The Burn was that galaxy-changing event in the backstory of Discovery season 3, when, in 3069, every warp core in the galaxy detonated. Warp cores use matter/antimatter reactions to do their thing.

ISS Enterprise 

Inside the wormhole, Book and Burnham encounter the ISS Enterprise, and Book says right away “ISS, that’s Mirror Universe.” When he says this we hear the Mirror Universe music from Discovery season 1.

The existence of the ISS Enterprise in this episode is a massive easter egg, which contains various other smaller easter eggs. These include the following:

  • The ISS Enterprise was last seen, in-canon, in the TOS episode “Mirror, Mirror.” So, chronologically, in both our world, and the Trek timeline, this is its second appearance. 
  • The bridge and sickbay of the ISS Enterprise are just the sets from the Strange New Worlds version of the Enterprise. Discovery season 5 filmed in between SNW seasons.
  • Several versions of the Terran Empire logo are seen throughout the ship. These match with the Terran Empire logo from Discovery season 1 and season 3, and differ from the logo from The Original Series
  • Does the redesign make sense in terms of the timeline? Well, Akiva Goldsman has suggested that on some level, the visual canon of Strange New Worlds relative to The Original Series isn’t the true canon. In 2023, he said that the aesthetic choices of the more modern Strange New Worlds don’t change the story as seen on TOS, but it doesn’t mean modern Star Trek will ever reveal a rubber-suited Gorn. “You will never see the Gorn like that…This is the Gorn as we perceive them,” Goldsman said. So, analogously, Discovery didn’t need to make the TOS Mirror Enterprise like the retro 1960s version. Plus, who knows what the Terran Empire did in between “Mirror, Mirror” and the moment this crew escaped? 

Mirror Spock 

Burnham mentions that the science station on the Enterprise was “my brother’s station.” This, of course, refers to Spock, who, in this universe, did, briefly, work at this exact station. Burnham says, “I’m sure he was just as ruthless as the rest though,” which, as we know, is not true. Mirror Spock spared Prime Kirk in “Mirror, Mirror,” and then became the leader of the entire empire.

In fact, when Book reads the story of this version of the Enterprise, he says, “The Terran High Chancellor was killed for trying to make reforms.” In the Deep Space Nine episode “Crossover,” we learned that the leader of the Terran Empire was Spock. And that Spock trying to reform the Terran Empire led to Earth being taken over in the 24th Century by the Klingon-Cardassian Alliance. 

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So, the episode references Spock, twice, without actually naming him, and the second time, neither Book nor Burnham even knows that Mirror Spock was a low-key hero.

Saru and the Mirror Universe From Discovery Season 3

Book mentions that the crew of the ISS Enterprise escaped with the help of a “Kelpien slave turned rebel leader.” This seems to reference the events of “Terra Firma Part 2,” from Discovery season 3. In that episode, Georgiou went back into the Mirror Universe and created a kind of pocket timeline in which she died at a different time, and Saru was freed to become a rebel leader. At the time, it wasn’t clear if this changed the timeline of the Mirror Universe — or the timeline of Discovery season 1 — but the mention of a Mirror Saru who is a rebel suggests that some version of that timeline might have occurred after all.

The Breen Revealed!

First mentioned in The Next Generation, the Breen eventually appeared in person in the 1995 Deep Space Nine episode “Indiscretion.” But, from that point, until now, they’ve only appeared inside their suits, and under those helmets. There’s been a ton of speculation for decades about what the Breen look like under their helmets, and now, we’ve finally seen the answer. 

In “Mirrors” — during the flashbacks that explains Moll and L’ak’s relationship — we finally see that the Breen have not one face, but two. Apparently, one face exists under their helmet, while another, more stable face can emerge when they have their helmets off. This seems to suggest that the Breen hiding their faces has more to do with a cultural tradition than any environmental requirement. Moll has been running around without a helmet this entire season, and apparently, that’s what a Breen can look like, too.

Smuggling Tribbles

In one of the flashbacks, Moll jokes about making sure she “didn’t smuggle any tribbles on board.” This seems to suggest that yes, even in the 32nd Century, tribbles are still possibly hazardous, because they breed so quickly, and overrun spaceships and space stations. Famously, the tribbles first appeared in the TOS classic, “The Trouble With Tribbles.” Though, in Picard season 3, we did see a genetically engineered “attack tribble” with vicious teeth, stored away in a Section 31 black ops lab. It’s possible this “attack tribble” was created during the Dominion War, which means, it might have been designed to fight the Breen, who were Dominion allies back then.

Hit it?

As Book is navigating the ISS Enterprise out of the wormhole, he says, “Should we hit it?” Book has no idea that “hit it” was Pike’s catchphrase to send a ship into warp. Burnham smiles sheepishly and responds, “Feels weird. Let’s just fly.” She feels weird because she doesn’t want to steal Pike’s catchphrase, and so she uses her own catchphrase, “let’s fly,” instead.

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The ISS Enterprise in the Prime Universe 

The episode ends with the ISS Enterprise being fully intact in the Prime Universe. We’re told that Detmer and Owo are flying the ship back to Federation HQ on their own. Scotty was able to fly the classic Enterprise with just himself and Sulu in The Search for Spock, so we have to assume that Detmer and Owo have done something similar. We don’t know if a new, 32nd Century Enterprise exists in this era of Star Trek, but as of now, Discovery just brought a classic version of the ship into the future. 

Because the upcoming Starfleet Academy series is set in the 32nd Century, it feels possible that Discovery just created a way for the students of future Starfleet to hang out on the bridge of the classic Enterprise — again!