It’s a slam-bang season finale, with some of the crew working to take back the ship from Osyraa and some more of the crew trying to save Su’Kal and learn the cause of the Burn. My take on Star Trek: Discovery‘s third-season ender, “That Hope is You, Part 2.”
I thought the bizarre alteration of people to a different species was a bit odd, but it does give us one of the best moments of the episode. The fear that Su’Kal needs to face in order to banish the monster and finally shut down the holodeck is the fear of being alone. He was just a child and the last one left alive, and he saw everyone else die—including his mother. We see the final recording of his mother dying, an event that so traumatized Su’Kal that it caused the Burn. (The reasons are given by Culber in a bio-technobabble infodump involving the radiation affecting him in vitro and dilithium and subspace and other such nonsense.) Su’Kal is reminded that he’s alone, but then he turns around and, for the first time, sees Saru as he really is: another Kelpien.