History TearJerker / TeenageMutantNinjaTurtles2003

** April's attempt to reason the crazed Stockman, trying to remind him about the time when he helped people and how brilliant of a mind he once was, trying to convince him that he can become that again, sparking Stockman's MyGodWhatIHaveDoneMoment. It's clear that April really admired her former boss and mentor, and still cares about him and feels pity upon seeing the state he has fallen into, even after he revealed his bad colors and tried to murder her after she uncovered his secret, and even as he's trying to kill her right now. When Stockman falls to his death alongside the cable car, April does cry in Casey's chest for a moment.

** The entire ''Good Genes'' arc, essentially, but also a special mention to Mikey trying to give monster Don cereal and juice, nearly losing his leg for it, and then just sadly saying, "I just wanted to give him some food..." It comes off as standard Mikey {{Cloudcuckoolander}} stuff, bordering on TooDumbToLive because he ''knew'' how violent monster Donncould be. But then you realize he's not only worried sick about his brother, but probably feels even ''more'' helpless than the others because as TheBabyOfTheBunch, basically all he can do is wait for the rest of the family and Leatherhead to figure out a plan, and he just wanted to ''do'' something to help Don. Seeing the normally-energetic Mikey so sad and lost-looking is tearjerking in itself. This ultimately works as the GodzillaThreshold, seeing how [[NoGoodDeedGoesUnpunished Mikey's attempt to feed his suffering brother resulted in him nearly losing his leg]], Leo decides they will have to work with Bishop to cure Don.

* "[[BadFuture Same As It Never Was]]." ''The entire thing''. It just goes to show that two episodes later, "The Real World Part Two", the waterworks start as Donnie hugs his brothers (one went into a superhero world, the other a intergalactic race) who have no idea what the poor turtle went through.
-->'''Donnie:''' Raph, you're alive! And Mikey, you have both arms!

** Donnie is also the one who emphasizes how millions will suffer if the Shredder succeeds now, painfully remembering his trip to the dark future where the Shredder had won.
** Donnie asks Honeycutt to blow the ship's core, and Honeycutt frets about what it would do. Donnie has a grim look, and Honeycutt realizes what he's asking. He laments that he had worried the situation was hopeless, hammering in just how terrible their prospects looked... but he agrees, and says he is with the Turtles and Splinter to the end.

** One particular moment is Donnie's frantic worry over Mikey when he dives into the whirlpool trying to save Klunk. Donnie himself nearly drowns trying to save him, and even when Leo and Raph manage to pull them to safety, all Donnie can do is ask if Mikey made it.

** For his part, Leo's surly demeanor is completely gone and finally he has lost the hardness in his voice he's had all season - but it's from the horror at what he's done. Leo realizes his anger and trauma have grown into something toxic and he agrees with the necessity of the trip, but he's also despondent over it and says he doesn't want to leave. At the same time, Raph, Donnie, and Mikey are all listening outside the door and looking at each other anxiously. The brothers are often portrayed very maturely in this series, but in this moment they seem ''young'', and it really drives home for viewers that they're not only still teenagers, but extremely isolated ones who have never really been apart from each other before.

* Leatherhead's voice-over intro in "Good Genes Part 1" perfectly sums up the horrible situation the turtles find themselves in with Donnie infected and turned into a monster:

-->''The other turtles look at Donnie in worry while Splinter closes his eyes and bows his head in sorrow.''

** The entire ''Good Genes'' arc, essentially, but also a special mention to Mikey trying to give monster Donnie cereal and juice, nearly losing his leg for it, and then just sadly saying, "I just wanted to give him some food..." It comes off as standard Mikey {{Cloudcuckoolander}} stuff, bordering on TooDumbToLive because he ''knew'' how violent monster Donnie could be. But then you realize he's not only worried sick about his brother, but probably feels even ''more'' helpless than the others because as TheBabyOfTheBunch, basically all he can do is wait for the rest of the family and Leatherhead to figure out a plan, and he just wanted to ''do'' something to help Donnie. Seeing the normally-energetic Mikey so sad and lost-looking is tearjerking in itself.
** The family has lost one of their key assets with Donnie's secondary mutation. Leatherhead is at the lair full-time but is struggling to contribute much, as Donnie did the majority of the work on the outbreak, and has only come to the discovery that the mutation is killing him, due to the outbreak mutagen reacting negatively to the Utrom mutagen already in his body. Splinter asks Leo what he's thinking, and Leo spells out how helpless they seem to be without Donnie.

** Leo even states in his [[PreviouslyOn voice-over]] [[TheTeaser intro]] before the second part of the arc that had it been any one of them as the monster, Donnie would have quickly found a way to cure them back.

* The fate of the Triceraton soldier, Zog, in ''Rogue In The House''. He was a regular loyal soldier sent to capture the Synthoid but was warded off by Federation soldiers and the Turtles and got separated from his troops, left to wander the sewers and made delirious from the gas beneath. After meeting the Turtles, he is tricked into thinking they're his superior officers to avoid a potential enemy and plans to kill himself for failing the mission before being convinced by the Turtles that the mission was a success and that he was still a valuable asset. After which the Turtles choose to help the Triceraton who proves highly loyal to the Turtles, even choosing to bravely fight the Shredder for them by his lonesome and sacrificing his life to defeat the Shredder and let the Turtles get to safety.

** Best moment is after he has kidnapped April, and begins to act as if it's the first day at work - and then gets a flashback of his mother lying in bed. He holds a large cable in his hands, kneeled next to it thinking it's his mother's hands and just cries for her not to leave him. It's heartbreaking. And then he starts to hallucinate even further, starting to see April as his mother, Stockman then tries to save who he believes is his mother out of the tipping back cable car, all the while calling her his 'momma' and telling her he loves her. And then the cable car then falls taking Stockman with it just before he could properly say farewell to his 'momma'. Oh, good god…
** Made worse in "Adventures in Turtle-Sitting", when the newly-revived cyborg Stockman drops to his knees and screams "Why couldn’t you let me finally rest in peace?! '''WHYYYYYYYYYYY?!"'''

** Leo even states in his [[PreviouslyOn narration before the second part of the arc]] that had it been any one of them as the monster, Donnie would have quickly found a way to cure them back.

** Leo even states in his [[PreviouslyOn narration before the episode]] that had it been anyone of them as the monster, Donnie would have quickly found a way to cure them back.