Star Trek: Discovery Season 3 Finale Ending Explained

This Star Trek: Discovery review contains major spoilers for the end of Season 3.

What a ride! The third season of Star Trek: Discovery was easily its most consistent and, dare I say, best yet? From the get-go, the series’ decision to vault its characters into the far future for its third outing proved itself a smart one, as the crew of the Discovery set about exploring this strange, new reality. The hour-long finale was a solid ending for the season, answering some questions we’ve had since the season premiere. In that way, “That Hope is You, Part 2” really was the perfect bookend to the premiere that started this far-future arc. That being said, the episode also set up some fascinating plot and character arcs for Season 4. Let’s break down all that happened in the Star Trek: Discovery Season 3 finale, and what it means for the bright future of this show.

We Finally Know What Caused The Burn

The big reveal in the Season 3 finale is the confirmation that it was a scared Su’Kal who caused The Burn when he was a small child. With Saru’s support and encouragement, Su’Kal faced the memory of the event: the death of his mother, when he was small. With her death, Su’Kal was all alone on the KSF Khi’eth, on a dilithium planet in an isolated nebula. His mother made Su’Kal promise not to turn off the holo until the Federation came. She couldn’t know that the Federation wouldn’t come for another 125 years.

Su’Kal is a polyploid, aka someone whose genetics were altered based on the environment around him. Because Su’Kal was born on a planet filled with dilithium, it gave him a unique connection to the element. The sonic scream he emitted upon losing his mother sent a shockwave through subspace that caused the Burn. Now that he is no longer in the nebula, it is unlikely a similar event will happen again. “I’d like to help repair what is broken, if I can,” Su’Kal tells Saru, when he learns the truth. Perhaps this isn’t the last we’ve seen of the Kelpien.

The Bridge Crew Saves the Day

This was another excellent episode for Team Bridge Crew, who use their relative freedom on an occupied Discovery to sabotage the ship’s nacelle, dropping the ship out of warp and allowing the Federation and its allies to catch up. The Bridge Crew does so believing that it will be a suicide mission, as Osyraa has cut off life support to the lower decks of the ship, and they only have one oxygen tank amongst them. It’s Joann, who apparently has very impressive lung capacity, who manages to complete the mission (with an assist from one of those little DOT-23 droids), taking the oxygen tank and leaving her friends to die (per their request). “I love you all,” she tells them, which would have been solid last words. However, once Michael regains control of the ship, she is able to restore life support to the lower decks before her friends/co-workers die. So that’s good.

Are Keyla and Joann Together?

These two have always been depicted as especially close, and the season finale had me wondering yet again if these two might be romantically linked. “You’re alive.” “So are you.” This is their conversation post-nacelle explosion. There are other people there who are also unexpectedly alive. We see them embracing shortly after. I don’t support the cultural reenforcement of romantic relationships as more important than platonic ones, but I do wonder what the nature of this relationship is. Generally, I hope both characters—and their dynamic—get more screen time in Season 4.

Michael Kills Osyrra

Of course dropping the ship out of warp is only part of the solution. The Discovery crew also has to regain control of the ship. This is Michael’s mission. With some help from Book, and via a very cool sequence in the backend of the turbolift, Michael is able to make it to the ship’s data core. She manages to get rid of Osyraa’s goons, but Osyraa gets the upper hand in the fight, literally pushing Michael into the data core. It looks like it might be the end for Michael (though I doubt any viewer actually believed it would be), until shots fire from within the core, taking Osyraa out once and for all.

Michael emerges from the ship itself, telling the Season 3 antagonist: “Unlike you, I never quit.” As a post-murder tagline, it’s not a great one—especially because Osyraa didn’t really seem to be quitting so much as losing in this moment—but the imagery that accompanies it, of Michael literally merging with Discovery to take Osyraa out, is thematically-rich. This has been a season of Discovery really evolving as a character in their own right, and it was nice to see the ship itself have a hand in the crew regaining control of the ship.

Book Can Pilot the Spore Drive

In one of the most game-changing moments of the season, the Discovery crew figures out that, because of ability to communicate empathically with plants and animals, Book can pilot the spore drive. They bet the farm on the conclusion, too, jettisoning the warp core while within Osyraa’s ship Viridian. Book is eventually able to figure out how to jump, but they barely make it away in time. While this was a cool moment in the episode, it is a much cooler reveal for what it might mean moving forward. Book has expressed an interest in joining Starfleet, but it hasn’t been clear what his role in the fleet or on the Discovery might be. His ability to pilot the spore drive certainly makes him invaluable to the Discovery and to the Federation as a whole.

Yeah, Stamets is Still Pissed at Michael

One of the minor, unresolved character threads left lingering at the end of Season 3 is Stamets’ anger towards Michael for forcibly removing him from the Discovery in the season’s penultimate episode. Frankly, Michael made the right choice. If Stamets had remained on the ship, then Osyraa could have forced him to use the spore drive and the Federation never would have been able to catch up. That being said, I can’t say I wouldn’t be pissed at Michael if I were in Stamets’ shoes. By physically forcing Stamets off the ship, she took the choice to stay and try to save his friends and family away from him. But them’s the breaks when you volunteer to be the universe’s sole spore drive pilot.

Gray Gets a Corporeal Form, Then Loses It Again

One of the chief joys of the Season 3 finale was seeing Gray gain corporeal form while in the holo-program, allowing people other than Adira the opportunity to see and interact with him. (Hugh takes the chance to give Gray a big hug!) The holo gave Gray the form of a Vulcan (if you were wondering, Adira is Xahean here), but, for Gray, it just matters that he can be seen. When faced with the dismantling of the holo, Gray tells Adira and Hugh that he doesn’t want to go back to before. “It’s not enough,” he says. “I’m stuck. Tal’s stuck.” Hugh promises that they will find a way to make sure Gray is seen, but when the episode ends, Gray is still invisible to all but Adira again.

Burnham Becomes Captain of the Discovery

Discovery churns through at least one captain per season and the ship ends the season with a different captain than it started with: Michael has replaced Saru as captain (at least for now). Saru has taken a leave of absence to help Su’Kal settle into his life on Kaminar. It’s unclear for how long. When Michael brings up waiting until his return to decide anything permanently, Admiral Vance pushes back, with Saru’s blessing. So will Michael be Discovery captain forever and ever? Frankly, the show seems to have left enough room for the writers’ room to make that decision later, as they are breaking Season 4.

The Federation is Back on Its Feet

The season finale was a happy ending, not only for the Discovery but for the entire Federation. With Osyraa dead, the source of the Burn discovered, and the Discovery equipped with two spore drive pilots, the future is looking promising. As Michael’s closing voiceover tells us, the Discovery is poised to bring dilithium to the worlds of the Federation that have been cut off since the Burn. With this new source, they will be able to properly rejoin the Federation. With this new mission outlined in the finale’s closing minutes, Season 4 seems to already have a new plot structure, one even more based on discovery and diplomacy than Season 3.

We also learned that Trill decided to rejoin the Federation, and the Ni’Var have opened lines of communication with the Federation back up. The fact that the Ni’Var responded to Michael’s request for help earlier in the episode, effectively coming to the Federation’s aid when they needed it the most, says a lot about their potential willingness to become part of the organization again.

What Does the Closing Quote Mean?

Star Trek: Discovery Season 3 ends with a tribute to Gene Roddenberry, and to his original vision for Star Trek, exemplified through the following quote: “In a very real sense, we are all aliens on a strange planet. We spend most of our lives reaching out and trying to communicate. If during our whole lifetime, we could reach out and really communicate with just two people, we are indeed very fortunate.”

Why did the series decide to end the season this way? As showrunner Michelle Paradise told Comicbook.com: “It emerged closer to the end of the post process as we were finishing post for the season and just recognizing that this was going to be airing at this particular time. And we just felt like it would be appropriate to have something from him. I mean, Gene Roddenberry, we’re only here because of what he did and because of the show that he created and there’s the baseline, the template that he established. And so it felt appropriate to have something from him, a quote from him at the end of our season. And that was one that resonated with us.”