The Changeling that impersonated Martok somehow miraculously survived, and he cooked up a convoluted revenge plot on Odo. By pretending to be one of the 100 baby Changelings the Founders cruelly sent out into the galaxy, Laas hopes to turn Odo against his humanoid friends and trick him into leaving DS9.
is a great episode that explores a great deal of what has gone unsaid on DS9 so far. The most unsettling truth is that the Founders are kinda right, the humanoid races are a bit racist towards them, and their ability to take any form does cause suspicion to be cast towards them. At the same time, Changelings like Laas are smug pricks. They view themselves as higher lifeforms and look down on us as limited beings that are destructive and dangerous. In time, Laas's disturbed form of Changeling pride would lead humanoids to hate his kind, and Laas would set out to kill them in his belief that he's protecting himself. Laas allows us to see the beginning of the Dominion without actually seeing it. Near the end, we get a vision of how it all started.
For Odo, this is an eye-opening experience. He has always been aware that he's treated as an outsider, Laas just forces him to contemplate it. He has become so accustomed to fitting in with humanoids that he doesn't realise all that he's missing by not shape-shifting all the time. His friends like and trust him, but maybe that's because Odo only relates with them in a humanoid shape. How would the likes of O'Brien or Worf react if Odo decided to have a conversation with them in the shape of a luminescent octopus, or a ball of flame? They may not be opposed to Odo acting in such a way, but it would make them feel weird and understandably uncomfortable, so Odo chooses not to do these things.
This is where my love of counting things comes in handy, because we can actually chart Odo's decline as a shape-shifter through the seasons.
Season 1: 6
Season 2: 6
Season 3: 3
Season 4: 13
Season 5: 3
Season 6: 2
Season 7 (so far): 1
As you can see, other than the random spike in shape-shifting in season 4 (which is inflated due to Odo taking part in Changeling drills), Odo's shape-shifting has been declining throughout the seasons. He has only changed shape on screen once this season, and that was a joke about his umpire outfit. (Also note that one of the shape-shifting occurrences in season 6 was when he "wore" a tux, and two of the occurrences in season 5 were jokes about his sexual anatomy and the appearance of Old Odo in Children of Time
.) Odo doesn't shape-shift much publicly any more. The real reason for this probably has something to do with shape-shifting being Odo's gimmick back in the early seasons and as he developed as a character the writers didn't need to rely on it any more, but Laas' claims do make a compelling case in-universe.
Anyway, the rest of this episode is about love and how it conquers all, especially the city of Troy. See, Kira loves Odo so much that she decides to let him go. That's not really my style of love, I come from the clingy if-you-leave-me-I'll-make-your-life-a-living-hell school of romance, but I appreciate the sentiment. Odo is so moved by this gesture that he realises not all humanoids are bad and that Kira is one person that he can truly be himself with. In a final romantic moment, Odo attempts to reveal his true nature to Kira, but he ends up smothering her with toxic fumes that make her imagine a magnificent light-show.
Form of... pure love: 35