Warning: SPOILERS for Star Trek: Lower Decks Season 5, Episode 9 - "Fissure Quest"

Star Trek timeline.

Star Trek: Enterprise, an Emergency Medical Hologram based on Dr. Julian Bashir (Alexander Siddig) and his lover, Dr. Elim Garak (Andrew Robinson), and Curzon Dax (Fred Tatasciore), all from Star Trek: Deep Space Nine, and Captain Lily Sloane (Alfre Woodward) from Star Trek: First .

Meanwhile, multiple versions of Star Trek: Voyager's Ensign Harry Kim (Garrett Wang) comprise the crew of Captain Boimler's Anaximander. They're ed by the lone Harry Kim in the multiverse who was promoted to a Lieutenant. Yet not all of these alternate reality Starfleet legends survived Star Trek: Lower Decks' sensational penultimate episode.

DS9's Heroic Curzon Dax Death In Star Trek: Lower Decks Explained

T'Pol Saves The Dax Symbiont For Its Next Host

Curzon Dax died heroically in Star Trek: Lower Decks season 5, episode 9, "Fissure Quest." Curzon came from a reality where he never ed the Dax symbiont on to Lt. Commander Jadzia Dax (Terry Farrell). Lower Decks' alt Curzon is the tactical officer of Captain Boimler's starship Anaximander. In Curzon's past life, he must have also been the United Federation of Planets' Ambassador to the Klingons because he hefts a bat'leth and loves to use it.

Sadly, Curzon was mortally wounded in defense of his crew after they escaped imprisonment by the Khwopians. To buy Captain Boimler and his friends time to board and launch the Anaximander, Dax fought off a host of feral Khwopians solo. Curzon didn't inform his crew he was seriously injured, and he collapsed on the bridge. Tragically, Curzon couldn't be saved, but T'Pol used a Vulcan mind-meld to transfer the Dax symbiont's memories into her brain. Curzon died knowing T'Pol was his friend, after denying their friendship the entire time they worked together.

Star Trek: Voyager's Lieutenant Harry Kim Died As A Villain

Maybe Harry Kim Shouldn't Be Promoted

Star Trek: Lower Decks season 5, episode 9's other legacy character death was Lieutenant Harry Kim, who turned into the villain of "Fissure Quest." This alt version of Harry tricked and kidnapped all of the Ensign Harry Kims when he stole the Beagle, the Quantum Reality jump-capable starship of Captain Lily Sloane. Lieutenant Kim's mad scheme was to bring his fellow Harrys to his reality where they could all be promoted.

To the Ensign Harry Kims' credit, they rebelled against Lieutenant Kim, who wasn't exhibiting "proper Kim behavior."

Lieutenant Harry Kim was dumbfounded that his alternate reality selves were never promoted in their universes. Lt. Kim seethed from the disrespect he perceived, even from Captain Boimler's crew. Filled with hubris because he's a Lieutenant, Harry refused to listen when the science was explained to him that his attempt to enter his Quantum Reality would blow up the multiverse. After the Anaximander beamed the Ensigns back aboard, Lieutenant Harry Kim continued with his attempt to return home and exploded along with the Beagle. Star Trek: Lower Decks' series finale must save the multiverse from the calamity the foolish Lt. Harry Kim caused.