Kol is uniting the houses, and in return for oaths of fealty he’s equipping their vessels with the cloaking technology he stole from T’Kuvma and Voq. Starfleet are taking heavy losses and Lorca has had enough. He dispatches Burnham, Tyler and Saru to Pahvo, a world where a seemingly naturally occurring crystalline transmitter could be modified to act as a means of detecting the cloaked vessels.

But Pahvo is not uninhabited. As Saru is about to find out…

With Discovery powering towards its mid-season finale, this episode, I suspect, got handed a lot of external elements to fit into place. We have Pahvo, the ultimate(ish) fate of Admiral Cornwell, another couple of twists in the L’rell plot, Tyler and Burnham’s romance, Saru’s colossal personal and professional frustration and the war.

The fact it pretty much all lands is testament to Kirsten Beyer’s skills as a writer and John S. Scott’s direction. The episode never slows down, and in an ideal world could certainly have used about eight more minutes but it does very well with everything that’s asked of it.

Meta-plot on down then, we start with L’Rell and Cornwell. This is a really smart, surprising series of events that puts the Klingon side of things on a far different footing than we previously thought. L’Rell clearly has a long game. In fact she probably has about six, but we don’t know what yet. Her desire to defect seems sincere, and that makes her apparent murder of Cornwell all the more shocking. There’s also some more breadcrumbs about Tyler and who he may or may not really be. These, in the hands of another show, would be massively annoying. Here, they’re timed perfectly.

Likewise the slow development of Burnham and Tyler’s relationship. There’s some fascinating work done here with their complementary damage and Burnham’s inescapable knowledge that life in prison waits for her at the end of the war. The possibility of being happy, let alone deserving to be, simply doesn’t occur to her and that’s one of the saddest things in the show so far.

And then we get to Saru and Pahvo and possibly the single misstep. Doug Jones revels in getting more to do and Scott’s depiction of Saru’s massive natural speed is really effective. Likewise the moment where Saru reveals he’s been ‘possessed’ is wonderfully creepy. The fact it’s bookended by the heart-breaking reveal that he wasn’t afraid for the first time in his life gives the episode an emotional uppercut you never see coming too.

But for all that, Pahvo itself feels a touch rote for the first time in the show’s run. The idea of a planetary networked organism is a good one but there’s a sense of unfinished business here that, having seen the next episode, I know we don’t get. The idea is great but the precedent is not. Trek is rife with energy cloud aliens who want to bring us love and adding another feels like the obvious choice in a show that hasn’t made any of those to date.

Verdict: This season of Discovery has been impressive since episode 3 and frequently great since then. This episode lands solidly between the two; a great idea, well executed and not smothered by the obligations of the arc plot. The unfinished business on Pahvo is frustrating but the episode as a whole is yet another excellent entry in Discovery’s freshman year. 8/10

Alasdair Stuart