A character learns that they're adopted and doesn't take it very well. Maybe they feel they've been lied to or maybe they worry about not being a "real part of the family". Either way, their feelings towards their parents become sour due to the fact they're adopted. The reveal of "I Am Not Your Father" and cries of "You're Not My Father!" are extremely common in these sorts of situations.
Other situations where a character dislikes their adopted parents, hates the fact they're adopted, or hates their to-be adoptive parents are allowed. If they had already lived a portion of their life with biological parents or other relatives, and only later did something occur to cause them to be adopted by people living elsewhere, perhaps they will try returning to their homeland/birthplace by going on The Homeward Journey. In more unfortunate cases, they may find themselves a Stranger in a Familiar Land. In more fortunate cases, perhaps they will experience a Childhood Friend Romance.
Inverse of Happily Adopted. If the discovery of being adopted leads to the adoptee searching for their biological parents, that's Gene Hunting. Compare and contrast Bastard Angst (where the child angsts about being born out of wedlock), Orphan's Ordeal and Adoption Diss.
- Mitsumi from Pokémon: Diamond and Pearl Adventure! was raised by the Big Bad Cyrus. they were raised to be a very powerful and violent Pokemon trainer but took a HeelFace Turn prior to the series. They've disowned Team Galactic and consider themself on a Last-Name Basis with their adopted father.
- In Revolutionary Girl Utena, Nanami, who has an incestuous crush on her older brother, is crushed and upset after her brother reveals that both of them are adopted. For some reason, the reveal that they are Not Blood Siblings ruins the magic for her, even though in anime-logic this usually makes their relationship more ok. The Not Blood Siblings aspect is further subverted when it turns out that they were adopted from the same family and are related.
- In Sarazanmai, Kazuki learns as a preteen that he is adopted. This causes him to grow distant from his loving family and brother, particularly after he meets his birth mother, though she seems happy with her new life. This angst is heightened after a confrontation with his brother after the birth mother meeting indirectly leads to the brother being crippled in a car accident, which Kazuki blames himself for and increases his withdrawal from his adopted family.
- In Sket Dance, the "Happy Birthday" arc is a flashback on how the main character Bossun learned he was adopted and the circumstances around his real parents' death. He fled from home in shock, but after a revelation that his parent' death wasn't in vain and confirming his adoptive mother truly loves him, he got over it.
- Rintaro from Stars Align feels like a unwanted burden to his adopted parents. This is due to the social and legal stigma against adopted children in Japan.
- Digimon Adventure has a small subplot involving Koushiro (Izzy). At some point prior to the series, he overheard his parents talking and thus found out he is adopted. This left him devastated, and although he didn't confront them about it, it caused him to retreat into his computer work in an attempt to ignore it and pretend that everything had been the same as before. In episode 38, his parents finally tell him the truth, and reveal the whole story; Koushiro's biological parents died when he was very young, and his current parents are his biological parents' cousins, who themselves lost a child of their own. They in turn are shocked to learn Koushiro has known the truth for some time now. It leads to a heartwarming scene where Koushirou thanks them for telling the truth to him, and his adoptive parents reaffirm to him that they only want him to be who he truly is.
- Hungry Heart: Wild Striker: Kyosuke Kanou had a loving, albeit complicated, relationship with his older brother Seisuke, whom he looked up to for teaching him to play and love soccer. But when he grew up, people started comparing them and Kyosuke felt that he was living in his brother's shadow, reaching the breaking point when he discovered by accident that they weren't biologically related (Kyosuke's parents died in a car crash when he was a baby, and he was adopted by his father's best friend). Part of his Character Development is to learn to cope with this fact and reconciling with his family.
- In Naomi, the titular character starts obsessing over a conspiracy regarding her town when Superman shows up one day and no media outlets reported on it. Naomi's psychiatrist rationalizes that this obsession is driven by the fact that she's adopted like Superman, yet there's seemingly nothing special about her whereas Superman came from another planet and is a hero beloved around the globe.
- In New X-Men, Quentin Quire's transformation from a normal student to would-be terrorist is kicked off when he discovers that he's adopted. Already facing ostracism from his classmates because of his serious demeanor, the knowledge that his birth parents apparently didn't want him crystallizes his belief that he is separate from the rest of the world.
- The Sandman (1989): In the Doll's House story arc, Miranda Walker is at first in denial after being told that she was adopted and that her benefactor Unity Kincaid is her biological mother.
- Downplayed in Superman: Secret Origin. Clark is horrified when he learns that he's an alien from another planet and flees into the fields above his parent's wishes. When Jonathan manages to catch up to him, Clark says he just wants to be the Kents' son. The Kents assure him that he is their son.
- In Neither a Bird nor a Plane, it's Deku!, Izuku doesn't take learning that he's an alien well, as it comes just hours after he nearly killed his best friend with powers he shouldn't have. He declares himself a monster and says that he isn't really the Midoriya's son, since he wouldn't have hurt anyone if that wasn't the case. He becomes a shut-in who refuses to come out of his room whenever possible. Eventually, he gets over his own angst enough to reconcile with Inko and Hisashi and considers them his real parents over his biological parents.
- A very popular Fandom-Specific Plot for The Loud House fanfics is Lincoln finding out he is adopted, and dealing with the fallout. Even the show itself jossing this theory in the Season 2 episode Not A Loud didn't stop fans from using it. Some of the more notable examples include Thicker Than Blood, The Little White Lie, and A Loud To Stay.
- Subverted in Return to Hinamizawa. The story opens with Miaka discovering that she is adopted, claiming that her parents "stole" her, and attacking her mother with a knife; but it's quickly revealed that this was under the influence of Hinamizawa Syndrome, and her real feelings are much closer to Happily Adopted.
- In Kung Fu Panda 2, Po finds out he's adopted (though it's comically obvious seeing as his adoptive father is a goose whilst he's a panda) and struggles with it over the film, especially when he learns his birth family were murdered by Lord Shen in an attempt to avert a prophecy foretelling his defeat. Po eventually accepts his past and becomes a stronger person, realizing that although his beginning was tragic he still had a loving upbringing with Mr Ping.
- In The Prince of Egypt, Moses does not take it well when he learns that he was Adopted into Royalty. Of course, this is largely because his adoptive people have been enslaving and killing his biological people.
- The title character of Tarzan was raised by gorillas after his parents were killed; although he has a positive relationship with his adoptive mother Kala, he initially struggles to integrate himself with the troop and is distrusted by their leader, Kerchak, who refuses to acknowledge Tarzan as his son even though Kala is his mate. Tarzan desperately tries to gain Kerchak's approval and is upset when he learns Kala never told him there were other humans out there, feeling increasingly torn between his life in the jungle and the possibility of rejoining human society. He ultimately stays in the jungle, though he's accompanied by his love interest Jane and her father, getting the best of both worlds. He also finally gains Kerchak's love and respect after saving the gorillas from poachers, though it's a bittersweet moment as Kerchak soon dies from a bullet he took for Tarzan.
- Anna from When Marnie Was There began living with her foster parents at age 5. She was happy with her life until she recently found records showing that they get paid money for fostering her. This upset Anna and caused her to become very self-conscious and introverted. After she Took a Level in Cheerfulness over the film and learned that her mother wanted to tell her but she didn't know how, and that she loves her money or not, she began referring to her mother as such instead of calling her "auntie".
- The Craft: Legacy: Lily freaks out when she learns she's adopted. It's very justified, because she finds out by stumbling across her adoption documents rather than her mother telling her and she's in her late teens by this point, so her mother had been keeping this from her for nearly two decades. Not to mention she finds out on the day of her boyfriend's funeral, after he apparently killed himself. She comes to terms with it in the end and sets out to meet her birth mother.
- In Flirting with Disaster, Mel is so consumed with angst over the fact that he was adopted that it's affecting his ability to care for his own son (he can't even commit to a name for the boy.)
- The main plot of October Baby involves Hannah having an identity crisis and going Gene Hunting after not only finding out she's adopted, but that her birth mother tried and failed to abort her, resulting in health complications later in life (her adoptive father also engages in tough love, which makes him comes across more as a controlling jerk). Hannah is disheartened when her birth mother is dismissive and doesn't want to get to know her, but eventually accepts it and reconciles with her adoptive family.
- In Thor, Loki reacts very poorly to learning that he was adopted, both because it focuses all of his buried insecurities about playing second fiddle to Thor and because it also reveals to him that he's been a Frost Giant, one of the Asgardians' ancient enemies, all along. Ironically, his adoptive parents had kept the knowledge from him specifically so he wouldn't feel Adoption Angst!
- In Brothers Conflict, when Ema finds a set of baby mementos displaying her mother's name along with some unknown man as the father, she's shocked and devastated, as her mother died when she was young so her Papa is all the family she's ever known. However, whichever love interest the player is pursuing appears to comfort her and convince her that blood relation isn't necessary since she's already been accepted by all her new brothers as well. The metaphor is sorta strained by the fact that, uh, they're all love interests, but Ema quickly changes tune and accepts that the man who raised her is still her beloved Papa.
- The Belgariad: Garion has a bout of this when he learns that the "Aunt Pol" who raised him is actually the legendary 3000-year-old sorceress Polgara, not least because it happens when she downplays their relationship to hide his status as The Chosen One. Zig-zagged later when she clarifies that she's his ancestor's sister and reassures him that she loves him immensely.
Garion's orphaning was complete now. He was adrift in the world with no ties of blood or heritage to cling to. Desperately he wanted to go home, back to Faldor's farm, where he could sink himself in unthinking obscurity in a quiet place where there were no sorcerers or strange searches or anything that would even remind him of Aunt Pol and the cruel hoax she had made of his life.
- In Midnight, Violet's brother Will just found out he's adopted, which causes distress for both of them. Will already didn't get along with their parents, especially their father, so he feels even more alienated from the family, while Violet fears Will won't view her as his sister anymore. It doesn't help that Will found out when his grandmother blurted it out during an argument, suggesting Will shouldn't be so 'ungrateful'. Will starts to come to terms with it after his parents open up to him about his adoption; they adopted him as an infant after his birth mother died of a drug overdose and their own son died of SIDS.
- A minor case occurs in the Agatha Christie novel Mrs McGinty's Dead, where Maureen Summerhayes says to Robin Upward: "I don't like being adopted, do you?" This statement proves to be crucial in identifying the real killer, as Poirot explains that the "Do you?" part indicated that Mrs Upward was not Robin's real mother, as Maureen would be able to recognise someone as being adopted due to being adopted herself.
- Shades of Magic: Prince Kell believes that his adoptive parents the King and Queen don't truly see him as a son, only a Court Mage for Prince Rhy; in his darker moments, he suspects they engineered his pre-adoption Identity Amnesia. His minor acts of rebellion against his perceived Gilded Cage end up catalyzing several major crises for the kingdom. Nonetheless, he loves his brother dearly, and refuses a chance to learn about his birth family.
- It's a subtle reoccuring theme in Warrior Cats for characters to stop seeing their adopted parents as their family after learning they're adopted. It isn't mentioned in-text, but several characters stopped referring to their foster/adopted parents as such upon the reveal.
- The Wildflowers: When her father first revealed she was adopted, Cat had a nervous breakdown and had to stay in hospital. This wasn't just from the shock of learning she was adopted, but also because her father had been sexually abusing her and claimed her not 'really' being his daughter made it fine. Cat starts feeling better about it after attending therapy and begins seeking answers about her adoption
- Kendall Hart on All My Children and Carly Roberts of General Hospital. Though they were adopted by otherwise good and loving people, their adoptive parents keep their adoptions from them until each girl inadvertently learns about it. Kendall and Carly feel displaced and like they don't belong in their adoptive families, resulting in their bitterness over their adoptions and their longing to meet their birth mothers, yearning for their approval and a place to belong. Hurt and embittered by their adoptions, both girls begin to resent their respective mothers over it and lash out. However, Kendall and Carly eventually develop close, loving relationships with their biological mothers, come to appreciate their loving adoptive parents and how they each have two mothers, and in Kendall's case, her adoptive father's role in her life.
- In Castle Rock, Henry Deaver struggles with being adopted, because he is black and his parents are white, leaving him as the only black guy in Castle Rock, meaning that he literally always knows he was adopted. While he loves his mom, Ruth, he hated his abusive adopted father, Matthew, and killed him when he threatened Ruth.
- Crank Yankers: In a Season 3 episode, Katie calls up a library to ask the librarian what does the word "mature" and "adapted" mean. Katie states, "My dad said I wasn't mature enough to know that I was adapted". The librarian claims that he must have said adopted, not adapted. Katie then has a breakdown crying and mourning that her parents are black who lied to her that it was just a "weird gene thing" and understandably the librarian frantically works to calm her down.
- CSI: NY has a bit of it with Ellie, Jos daughter. In her case, she knew she was adopted, but got upset at Jo not telling her the truth that her birth mom was in prison.
- Eastenders: This is the impetus for tragic consequences with both Donna Ludlow and Danielle Jones. Both were adopted by normal, happy couples but both daughters ended up feeling out of place and longing for their birth mother. Donna was rejected by her mother, Kathy, who revealed she was the result of a violent rape when she was fourteen. Donna ended up going off the rails, lying and conning everyone in the Square, before taking her own life from a heroine overdose. Danielle was also the result of a teenage pregnancy which her mother, Ronnie, wanted to keep but was manipulated by her abusive father Archie into giving up for adoption. Danielle is hit by a car only minutes after Ronnie discovers Danielle's true identity and she dies in her birth mother's arms.
- In Friends Monica and Chandler are looking to adopt, so they visit a couple with an adopted child to learn about any special issues that might come up. Chandler tells the child he is adopted, which he didn't know before- then he lets slip that there is no Santa Claus. And he reveals to Phoebe's brother's triplets that Phoebe is their birth-mother.
- One episode of House, M.D. sees a teenage patient become mysteriously ill with what looks like the early stages of multiple sclerosis. It later turns out that he was adopted, and his adopted parents were so concerned with making sure he never found out that they didn't bother to check out his biological mother's medical history, and thus didn't know that she wasn't vaccinated against measles, to which the patient was exposed as an infant. The infection went into a latent phase, turned into subacute sclerosing panencephalitis, and is now killing him. Thankfully, House manages to treat it before it kills the patient.
- The third season of Jane the Virgin reveals that Rafael Solano is adopted, which causes a great personal crisis (since they had a tumultuous relationship with their overbearing father), a financial upheaval, and a largely unsuccessful search for their birth parents.
- One episode of Law & Order: Special Victims Unit sees a poor kid dragged into a custody battle after Cragen discovers that he's the biological son of a murder victim in a cold case. Being adopted doesn't bother him too much, but finding out that his biological mom was murdered and that his biological grandparents think that his adoptive parents stole him causes him some emotional turmoil.
- The show Once Upon a Time is kicked off because Henry discovers he was adopted by the Evil Queen, and he is looking for his birth mother. His sense of alienation does wear off over the course of the series, coming to love both of his mothers.
- In Peaky Blinders, Michael never felt that he fitted in with his adoptive family, hated life in the quiet village he grew up in and dreamed of meeting his birth family. The fact he was likely sexually abused in foster care before his adoption doesn't help. Upon finding out his birth family are powerful gangsters and that he was forcibly removed from his loving mother (he was falsely told she was abusive), Michael leaps at the chance to rejoin them and never looks back.
- Parodied on 3rd Rock from the Sun, when Tommy is inventing Earth identities for the aliens:
Tommy: Harry, you're adopted, but we haven't told you yet.Harry: Oh... that's gonna hurt.
- A variant in Veronica Mars. Mac was actually Switched at Birth with Alpha Bitch Madison Sinclair (and they found out and kept it that way), but she clearly wishes she had been switched back, as she is so different from her parents and the Sinclairs are extremely wealthy, while the Mackenzies are poor. She's happy about knowing she was adopted, but she's not happy the adoption stayed the same.
- A major part of Jeremy's character in White House Farm is feeling he was treated differently than if he was blood related to his parents. He lashes out at his cousin Ann over this, claiming she feels entitled to the inheritance left by his parents because she's blood related and he isn't. As this is based on a real case it's ambiguous if this was true or just part of a persecution complex of Jeremy's, to the point he is eventually convicted of his family's murder.
- Mischa Bachinski of Ride the Cyclone is a teenage refugee from Ukraine who was unhappily adopted by a Canadian couple. His birth mother (who was dying of radiation poisoning from cleaning up the disaster at Chernobyl) gave him up in the hopes that he would have a better life in Canada, and she falsified Mischa's birth certificate to facilitate the process. His adoptive Canadian parents thought they were getting a cute little two-year-old. Instead they got Mischa, with a "five o'clock shadow and a hint of alcohol on his breath." Since they can't send him back they do the next best thing and ignore him — leaving meals outside his basement room and shooing him away "like a housefly" whenever he tries to speak to them. This turned Mischa into "the angriest boy in town."
- The rebellious Vivica in Growing Up can't bear to stay with her Amazingly Embarrassing Parents, who are "too nice" to her and dote on their biological son, whom they had after adopting her and realizing they could still conceive a child. She's trying to search for her birth parents to discover her origins, but their fate is left unknown by the end of her route. She'll still look for them unless you convince her that her adoptive family genuinely loves her, and her relationship with them will improve because she'll accept that they love her the way she is.
- Rock from Harvest Moon: A Wonderful Life is adopted, however he acts like he doesn't realize it. He loathes whenever people bring up how he doesn't resemble his parents (who are not even of the same ethnic background as him).
- Played for Laughs at the end of the Jacksfilms "How to tell your kids they're adopted" YIAY, where the last answer is "Tell them they have something in common with Jacksfilms." Jack gives a little "What?" and then sad, contemplative music starts playing and Jack spaces out as he stumbles to say, "Good one guys..."
- Adventure Time: In his backstory, Finn was raised by a family of talking dogs after the parents found him as a baby. Though he loves his adoptive parents, Margaret and Joshua, he also angsts over not knowing where he came from or who his birth parents are, all the more punctuated by the fact that he's never met another human being. When he does eventually meet his biological father, he is disappointed to find that Martin does not actually care about him. He does eventually meet his biological mother as well.
- One episode of Camp Candy has Vanessa receive a letter from her parents. It gets damaged before she can read it and it seems to reveal she was adopted. She spends the rest of the episode angsting over it and even runs away. Nurse Molly doesn't see the problem with being adopted since it means her parents specifically chose her. (But now Iggy angsts over his parents being stuck with him.) After Vanessa sees the light, it turns out she's not adopted, but her family's new puppy was.
- Ninjago: This turns out to be the motivation for The Quiet One, the leader of the Sons of Garmadon biker gang in season 8. They were a child when their parents were killed, and while it's mostly the trauma of that event that drives them, they were quickly adopted by a loving couple who treats them every bit as their own child but still conspire to murder them and angrily declares "They were never my parents!"
- Rocko's Modern Life: In "Who's For Dinner?", when Rocko meets Heffer's family (who are all wolves), he lets it slip that he didn't know that Heffer (a steer) was adopted, causing Heffer to go through this. For bonus points, the Wolfe family originally planned to eat Heffer (according to Peter, George even used to call him "Steak"), but grew to love him and adopted him, passing off the cuts of beef on his body as a birthmark. Heffer eventually comes to accept the Wolfes as his real family when he meets the spirit of his real (living) father, who reveals that he disowned him for being ugly, as he did with Heffer's real brothers and sisters.