Discovery and the Emerald Chain ship (which is still outside the shield) attack the Federation Fleet (pretty sure an entire Starfleet fleet and a space station should make quick work of these two ships, but for some reason, they don't). When the shield around HQ begins to fail, the Ni'Var arrive, having gotten Burnham's message sent to her mother in the previous episode and sent an entire fleet of their own. Osyraa calls for her ship to release pesticides and target shuttlebays, airlocks and "intakes" (what about this plan makes sense in the vacuum of SPACE and ships that have forcefields? What "intakes" is she even talking about? What would space ships have "intakes" for?), but Burnham convinces her to allow her to talk to the Admiral and gets BOTH fleets to stand down, allowing Discovery and the Emerald Chain ship to leave at warp (unable to use the Spore Drive due to Stamets being on the Starbase), but the two fleets give chase. Osyraa lets the air leak out in areas of the ship to slowly kill the crew (so she's just a one dimensional stereotypical villain, why not just vent the atmosphere?) but the crew manage to disable one of the warp nacelles by destroying one of the magnets (really? just magnets? they don't have something a little more advanced than that? This seems like an obvious and easily exploitable weakness in the separated nacelle design by just disrupting the magnetic field) holding it to the ship, causing Discovery to drop out of warp. But it's immediately taken into the Emerald Chain ship's hangar bay (why didn't the Federation and Ni'Var fleets immediately catch up when they were right behind them?)
Meanwhile, Michael and Book have a big fight with Osyraa and her henchmen in the turbolifts (which don't have doors, or they're left open for some reason, and this all takes place in a MASSIVE wide open area of the ship, like we've seen in previous seasons. Which I guess would make a little more sense in this season, since we know from Enterprise, they have technology to make ships bigger on the inside than they are on the outside by this century... But this is still one of the dumbest visual things they've done in this series. It doesn't make any sense for the ship to have a massive city sized void with only turbolift tracks running through it. A starship would utilize all the space they possibly could in the ship. Not to mention, on the schematics of the ship they have on displays, which ironically enough, they even show on the turbolift's controls in this very scene, never shows a massive void in the ship like this. Why do these creators keep putting stuff like this in the show? It makes no sense). After moving their fight to the computer... I mean "data core" room (which is clearly the Starfleet HQ set redressed), Burnham shoots and kills Osyraa (an anti-climatic finish) while nearly drowning in a wall of programmable matter Osyraa pushed her into (you'd think the programmable matter would have some safety features to prevent somebody from being completely enveloped by it).
Burnham resets the computer (I didn't mention this for the previous episode but the Emerald Chain changed the computer to their own OS, which is why the Sphere Data downloaded itself into the Dot Droids... Even though they couldn't delete the Sphere Data and said they were just going to ignore it since it was disguising itself as an old movie. For some reason Burnham uses a 23rd century backup... Which doesn't make sense, their computer shouldn't even be compatible with the 23rd century software anymore, why don't they have 32nd century backups?) and beams the remaining Emerald Chain people off Discovery (save for the human scientist in a hover chair, which the computer apparently could somehow tell isn't with the Emerald Chain anymore) and restores life support. She then asks any crew that can hear her report to the bridge (I guess most of the crew died, because besides the bridge crew... not that many people are on the bridge). Tilly gives command to Burnham... for some reason.
To escape from inside the Emerald Chain ship, she comes up with the brilliant plan to eject and detonate the warp core... and use the spore drive to jump out with Book as the pilot (why would she suddenly believe he'd have the ability to pilot the spore drive? He doesn't have space tardigrade DNA, which has been established to be required for it. They come up with this theory his empathic abilities with animals will allow him to connect with the spores out of nowhere... Which they're betting their lives on before they even test this theory. Spores are also not animals... they are a reproductive cell from fungi, how can he "connect" with them? I don't recall them explaining that's how it works for Staments... Not that how the Spore Drive works makes any sense anyway. And why detonate the warp core? With Osyraa dead, shouldn't they give the Emerald Chain the chance to surrender and release Discovery before they murder the entire crew? They just assume they wont release Discovery at this point). It works (inexplicably, albeit the writers try to mislead the audience by having the ship jump at the last possible second as the warp core explodes. The warp core I also want to point out bounces and sparks along the ejection tube... I'd hate to think that's a normal ejection, seems like it could cause the core to breach. And even the way the Emerald Chain ship is destroyed doesn't look right. The hull visibly expands, then contracts a bit like the ship is collapsing in on itself... which wouldn't happen in a vacuum, and then it explodes, like it withstood the detonation of the warp core before a secondary explosion destroyed it), and the crew goes to save the others left behind in the nebula.
Saru decides to return to his homeworld with Su'Kal to help him adjust to life in the real world, and so Burnham is promoted to Captain of Discovery (despite proving time and time again she isn't suited to be in command?). With Osyraa dead, apparently the Emerald Chain has fallen apart. Some worlds, such as Trill, have rejoined the Federation, while others, like Ni'Var are in talks about rejoining (you'd think they'd mention if EARTH was one of these planets that have rejoined or is thinking of rejoining, still disappointed they had Earth leave the Federation in the first place...). Starfleet has figured out how to mine the dilithium on the planet in the nebula (and apparently is so abundant on this planet that all their dilithium shortage problems are solved? That seems extremely far fetched), and so Discovery (FINALLY getting new 32nd century uniforms. And I guess medical has its own division color now? Hugh has a white stripe on his uniform instead of blue. Tilly is in a blue uniform, despite being a command officer Edit: Apparently this was digitally edited, she was filmed in a red uniform, but they changed it to blue for some reason. Adira gets a Starfleet commission, and is in a blue uniform. Book, despite expressing an interest in joining Starfleet, remains in civilian clothes) sets off to start delivering the freshly mined dilithium throughout the Federation.
This is yet another episode to get a title change, originally being "Outside" and is now "That Hope is You, part 2"... making a continuation of the first episode of this season? I've never seen a show have a part two that takes place 12 episodes apart like this... Let alone doesn't really directly continue the plot of that particular episode. But then Discovery already kinda did that with "Unification III"... which I and II weren't even Discovery episodes, they were TNG episodes.
Few other points...
Apparently the three Sphere Data Dot23 droids that were set up to help the crew out in the previous episode do absolutely nothing. Two of them get destroyed right away, and one helps save the crewmember that disabled the warp nacelle and I guess is seen being fixed at the end... But that's about it. I don't understand why the Sphere Data transferred itself to these droids in the first place. Last season they'd said it couldn't be removed or deleted from Discovery's computer... Granted the Sphere Data could conceivably remove itself, but why now? It probably could have done more to help the crew if it stayed in Discovery's main computer, and they established the Emerald Chain couldn't delete it. I get the feeling this was merely plot convenience, so the Sphere Data wouldn't be able to just take control of the ship away from the Emerald Chain... But the way these writers handled it makes no sense given what they'd already established about the Sphere Data. They'd obviously wrote themselves into a corner here.
They sorta expand on how Su'Kal caused the Burn. Hugh speculates that Su'Kal is a polyploid having been mutated in the womb (which still doesn't explain anything, a polyploid just means he's got extra chromosomes. Unless maybe the writers think one of those chromosomes could be an X-gene giving him super powers? In which case, they're writing for the wrong franchise...). Having been mutated in this environment with so much dilithium around, he somehow has a genetic connection to subspace because dilithium has a subspace component. Oh, and dilithium apparently has a subspace component to it. I'm sure no other Star Trek has ever said that dilithium crystals have a "subspace component" to them before. And that really doesn't make any sense... This is so dumb. I have to wonder if these writers know what the crystals function in a warp core even is given this explanation. So when Su'Kal's mother died in front of him, and he screamed in his grief, his voice traveled not only as a wave through the air, but also as a wave through subspace, and that for some reason effected all the dilithium throughout the entire galaxy in fractions of a second. So very, very dumb. Even traveling through subspace, we have never seen anything in Star Trek that can move across the entire galaxy that fast or is that potent with that kind of range. They seem to believe getting him away from this planet will prevent another Burn from happening, but what evidence do they have to support that? Is the dilithium on the planet amplifying the effect, and yet, why wasn't any of the dilithium on this planet rendered inert like the rest of the galaxy? I'm very disappointed this is the reason they came up with for the Burn. It's very poor reasoning, the timeline of these events doesn't really make sense, and how this subspace components stuff is explained doesn't make any sense in-universe.
Come to think of it... Su'Kal being raised in essentially a holodeck all alone, reminds me of TNG episode "Future Imperfect". Only, that was way better than this. And the action portion of the episode I've seen some people comparing to "Total Recall".
When this ship scans Adira to change their appearance (I don't recognize the species it makes them, I'm guessing something original to Discovery Edit: She's a Xahean introduced in season 2 of Discovery, although the makeup looks different), it also manifests Gray (who appears as a Vulcan) as a hologram that the others can see... somehow. Before they shut down the program, Gray is disappointed others wont be able to see him anymore, feeling this is what he is missing... I mean, Gray is easily one of my favorite characters introduced this season, but as a Trill, I'm not really sure what he expects here. He died and lives on because his memories are a part of the Tal symbiont, and it's really unusual the ship could and did manifest him as a hologram. Nevertheless, Hugh promises to find a solution to allow Gray the same autonomy. I'd think it'd be easy enough for another Federation starship to replicate however this ship was able to manifest Gray in the first place... But I would have liked for this to get a bit more focus here. This all felt really rushed and they move on too quickly.
Besides the little bit of character development for Gray and Adira here, and the tension of having a ticking clock for the crew to come back to save them... I don't see why the writers kept these characters trapped on this planet, they don't really add anything to the story that they didn't already cover in the episode "Su'Kal". We already knew Su'Kal caused the Burn, and it was apparent it was the death of his mother that upset him over 100 years ago. So why play that all out again? Granted I think it was done better here, albeit expanding on Su'Kal being "genetically connected to dilithium" is dumb, but still, they're essentially just repeating what we already knew from the earlier episode.
This is the first, and only episode of season 3 to show Discovery actually using its conventional warp drive, having exclusively used the spore drive the rest of the season. What happened to promising the jahSepp in season 2 that they'd NEVER use the spore drive again, because it was damaging the ecosystem within the mycelial network? They never so much as mentioned it this season, yet both Starfleet and the Emerald Chain expressed an interest in making more ships with a spore drive. You'd think the Discovery crew might have brought up they shouldn't be using the spore drive at all...
I hate this show. These writers always take dumb jumps in logic and can't seem to write a coherent story, rip off other better stories, and not to mention don't understand how things work in Star Trek. I don't know why it's getting a season 4...