Halfway through the season, this episode is a bit of a hodgepodge. Several storylines are advanced, but it feels a bit jumbled and the editing is choppy, especially through what was supposed to be a suspenseful moment. I didn't like all the jumping around, anyway. What's surprising is that Jonathan Frakes directed this, and I didn't think he would pull such stunts as that (although admittedly I don't know how TV works; do directors typically edit their episodes?). Anyway, although there were good moments, the whole thing felt a bit overstuffed. It's not one of my favorite episodes of the season.
To break down the various storylines: Hugh Culber is trying to find out what's wrong with Empress Phillippa. Naturally, she's a terrible patient, spewing out threats and insults to hide the fact that she's genuinely frightened. She has no idea what's happening or what she's flashing back to (although I noted in the flashbacks that she seems to be a good bit younger than she is now). Culber and the another doctor, Pollard (is she the chief medical officer?) try to scan her in the medbay, and she nearly "redlines." She snaps out of that screaming, then seizes one of the small sensors placed on her head and leaves. Later she overrides a security protocol and views the results, and jumps to the conclusion that she's dying. Culber intercepts her, proclaims that "it's not that cut and dry," and ushers her away to talk about it. We never see that conversation, so presumably whatever revelation Culber has for Georgiou will play out next week.
Stamets and Adira are looking through the SB-19 data Michael got last week, and narrowed the source of the Burn to a nebula. A signal is coming from this nebula that, according to Adira, "sounds like music," and turns out to be that ubiquitous melody that everyone in the future seems to know. Once filtered down, it becomes a Starfleet distress signal. Stamets says Adira can write an algorithm to decode it, and afterwards Adira quietly declares that they wish to be known as "they" now, that "I've never felt like a she." Stamets simply nods and says "Okay." Stamets and Adira are forming quite the nice relationship; Adira is playing their cello in a later scene, and he comes in to the rec room where they are sitting. Adira confesses they no longer hear their boyfriend Gray anymore, and it bothers them. Stamets starts to play the piano with them. Towards the end of the episode, Culber joins Stamets and an exhausted Adira in the engine room, where Stamets covers Adira with his jacket in a nicely parental moment. Culber also starts calling Adira "they" without missing a beat.
(And for those who say that, hey, this is the 32nd century and such things should be taken for granted and not even remarked upon, well sure, that's true in-universe. Hell, the universal translator should automatically register everyone's pronouns, especially alien species who might have multiple genders. However, this show is made not in the 32nd century but in ours, and the discrimination trans and/or nonbinary people face is such that it damn well needs to be shown and remarked upon.)
Tilly seems to be settling into her new role as acting first officer, walking with Saru down a corridor as they discuss various issues with the day-to-day functioning of Discovery. One very cute bit of this is Saru's attempt to figure out his "command phrase." He tries Captain Pike's "Hit it," as well as "Execute," neither of which go over too well. Towards the end of the episode, he finally seems to settle on "Carry on," which sounds a little prim and British for such a deliberate, laid-back alien. We shall see.
The main storyline is Book being summoned back to his home planet of Kwejian (pronounced "qway-john") by his hitherto unmentioned brother Kyheem. Book (whose name isn't that; it's "Tareckx"--apparently he adopted "Cleveland Booker" after he left) left fifteen years ago when Kyheem began cooperating with the crime syndicate the Emerald Chain, capturing tranceworms in exchange for a restraint against the native "sea locusts" of the planet that destroy the harvest. (My thought: what the hell are they doing depending on one crop? It's not explicitly stated that it's only one, but every time it's mentioned it's stated as "harvest," singular. And why can't they grow their crops under some sort of force field or dome to keep the sea locusts out? One can't think about this premise very much.) Of course Michael agrees to go with him. At least this time, instead of tearing off into the blue ignoring orders as she did previously, Michael, Book and Saru consult Admiral Vance. He permits Discovery to go, with the condition that they strictly "observe."
Naturally, that doesn't...work out. Mainly because of the leader of the Emerald Chain, Osyraa, who is such a (one-dimensional, if well-played) villain that she feeds her nephew to a tranceworm for allowing the Andorian, Ryn (from episode 6, "Scavengers") to escape. We find out that is why she is putting pressure on Kyheem and his planet, because she saw Ryn escape with Kyheem's brother, and she's trying to lure Book back to use him as leverage to recapture Ryn. (Why she wants Ryn isn't revealed until the final moments of the episode: the Emerald Chain is running out of dilithium, and Ryn is the only one who knows it. Only he tells Tilly, and now the Federation will know it.)
Saru tries to banter and bluff Osyraa once she arrives at Book's planet, but she doesn't fall for it, instead starting to blast the planetary defense systems to force Book and/or the Federation's hand. This catches Saru between a rock and a hard place: he was ordered to observe, but he can't stand by and watch this planet and people destroyed. To his credit, he's about to disregard Admiral Vance's orders when Tilly comes up with a solution: what if a "rogue officer, to be severely disciplined later," steals Book's ship and starts firing on Osyraa's warship instead?
This leads to an exhilarating action sequence where Kayla Detmer pilots Book's ship, shoots the hell out of Osyraa's ship, and in the process gets some of her mojo back. (The Andorian, Ryn, also volunteers to guide her, pointing out the Viridian's weaknesses, and there is a bit of comic relief when Book's cat Grudge jumps into his lap in the middle of the battle. "What the hell is this? What's that noise it's making?" Ryn shouts. "It's a cat," Detmer says. "Is that like a pet?" Ryn babbles. He doesn't put Grudge down though.) We had seen a brief scene earlier where Detmer was trying to modify the blue nanotech goo that is her new control console on Discovery, and on board Book's ship she converts it to full manual control. Two joystick-looking handles emerge from the console, and Detmer exclaims, "This is how I learned to fly!" as she dives in, swoops around, and blows up Osyraa's weapons center.
Osyraa finally retreats (although I'm wondering what's to stop her from fixing up her warship and returning after Discovery leaves) although not without basically declaring war on the Federation. One wonders what Admiral Vance will make of this. Finally, the problem of the sea locusts is solved: both Book and Kyheem had stated earlier that even though they are empaths, they are not strong enough to ask the locusts to move back out to sea. Michael (of course, as she's the star of the show--and this had me rolling my eyes a bit) comes up with the solution: use the Discovery to somehow, err, amplify the brothers' empathic powers on the, err, sea locusts' frequency, to enable them to communicate with the entire population at once. This was more than a little hand-wavy, and almost pulled me out of the story altogether. Nevertheless, as hokey as it sounds, it works.
Afterwards, Kyheem and his son visit Book on board Discovery, and Book admits he admires what the Federation is doing. He says he wants in. Michael instructs him to go to Saru and clear it with the captain, but she's obviously very pleased by this development.
I really wish this episode could have been edited a little better, as its quick-cutting choppiness was a bit off-putting. However, the next episode promises to get to the heart of what's going on with Phillippa Georgiou, which should be appropriately psychotic.