''Catalyst'' is a 2002 novel by Laurie Halse Anderson. The story takes place in the same universe as Halse's acclaimed novel {{Speak}}, a year after the events of that novel, and focuses on senior Kate Malone as she makes plans for college.

Kate is a preacher's daughter who excels in chemistry and is a star track athlete, with her sights dead-set on getting into the Massachusetts Institute of Technology once she graduates from Merryweather High School. She's so determined, in fact, that it's the only college she's applied to. Her getting rejected is just the tip of the iceberg, however, as soon afterwards a fire renders her neighbors - her abrasive school nemesis Teri Litch, Teri's mentally unstable mother, and her adorable toddler brother Mikey - homeless, and Kate's father arranges for Teri and Mikey to move in with his family. Kate must now struggle to deal with her rejection from MIT and a less-than-pleasant new roommate, all while maintaining her sanity.
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! Provides the following examples:


* AbusiveParents: Teri's father turns out to have been abusive towards both her [[DomesticAbuser and her mother.]]
* AdultsAreUseless: Jack Malone tries [[spoiler: and fails]] to help Teri Litch and Mikey, while ignoring that his daughter may need some guidance following her rejection from MIT.
* TheAce: Kate - stellar track athlete, budding chemist, mathematics expert - in her eyes, a perfect candidate for MIT.
* BreakTheHaughty: At the start of the story, Kate is certain of her chances to get into MIT. Her world abruptly falls apart when she's rejected, but she gradually comes to learn that life could be much worse.
* BrickJoke: As Kate watches Melinda's art class put up a sculpture in the hallway, she notes to herself that the plastic heart glued to the front of it will be the first thing to get ripped off. Several chapters later, she passes by the sculpture again and sees that the heart is gone.
* CallingParentsByTheirName: Teri refers to her deceased father by his first name, Charlie. It's later revealed that he wasn't a very good person.
* CheerfulChild: Two-year-old Mikey Litch is perpetually adorable.
* [[spoiler: ChildByRape: Mikey is both Teri's brother ''and'' her son.]]
** [[spoiler: ParentalIncest]]
* CloudCuckoolander: Betty, an elderly neighbor of the Malones and the one to take in Mrs. Litch after the fire, claims she talks to {{Jesus}} in her television. Then there's Mrs. Litch herself, a more tragic and serious example.
* TheCameo: Melinda Sordino, the protagonist of {{Speak}}, makes a brief one - just long enough for the audience to learn [[spoiler:how much better she's doing]]. Kate can't seem to remember her last name, instead calling her "Melinda Something" in the narration.
* ChildrenAreInnocent: Mikey. The biggest problem he ever ends up causing is an exceptionally filthy diaper.
* DeadPersonImpersonation: Kate pretends to be her deceased mother when she calls MIT's enrollment office to find out why she was rejected. [[spoiler: They realize who she is and wish her good luck.]]
* DisappearedDad: Teri's father is not in the picture, having died in jail after attacking his wife with a baseball bat [[spoiler: and impregnating his daughter.]]
* TrashTheSet: [[spoiler: For Teri, part of the grieving process over Mikey's death involves smashing her partially renovated house with a sledgehammer.]]
* DueToTheDead: [[spoiler: Still in shock immediately following Mikey's death, Kate and her friends stay at the Litch house after everyone else has left, lighting candles and fingerpainting the walls. A few chapters later, Mikey's funeral is attended by dozens of people, some of whom Kate wouldn't have expected to see there.]]
* FreudianExcuse: Mitch deconstructs this for Teri:
--> "We're all sorry that [[spoiler: Mikey died]] but that doesn't give you permission to be mean to Kate or steal her stuff."
* GoodAngelBadAngel: The protagonist's "Good Kate" and "Bad Kate" function this way throughout the story.
* HeroicBSOD: Kate's immediate reaction after receiving the rejection letter from MIT. Also [[spoiler: Teri, after Mikey dies.]] In this case the results are much more dramatic and violent.
* IdiotBall: Kate not applying to safety schools; it's so bad that Mitch doesn't even call her out for it because he knows she is hurting badly already.
* [[IllGirl Ill Boy:]] Kate's brother, Toby, is implied to have been plagued with respiratory problems since he was very young.
* InfantImmortality: [[spoiler:''Painfully'' averted - Mikey wanders off by himself while everyone's distracted and ends up being electrocuted.]]
* ItsAlwaysSunnyAtFunerals: [[spoiler:Mikey Litch's]] funeral is held on a beautiful sunny day. Kate lampshades this, commenting on how "obscene" it is to bury a body on such a day.
* IvyLeagueForEveryone: Subverted, much to Kate's disappointment.
* TheMourningAfter: Jack Malone, who once told someone that he buried his heart along with [[TheLostLenore his wife.]]
* NoNameGiven: Teri's mother is only ever called Mrs. Litch.
* NowWhat: Kate spends most of the book in HeroicBSOD, and she still doesn't have any college plans. She decides to start putting her life back together by [[spoiler: helping Teri with her plans to put ''her'' life back together.]]
* PromotionToParent: Teri has largely taken on the role of caring for Mikey, seeing as Mrs. Litch is...not entirely there. [[spoiler: Ultimately averted - Teri ''is'' the parent.]]
* SharedUniverse: As mentioned above, with ''Literature/{{Speak}}''.
* StickyFingers: Teri, who unabashedly steals (and wears) Kate's watch, and later the necklace her boyfriend Mitch gave her. [[spoiler: Mitch takes offense to this, on Kate's behalf.]]
* [[TellMeAboutMyFather Tell Me About Our Mother]]: Toby asks this of Kate, when he decides he wants to write about the deceased Colleen Malone for a school project.
* TheCobblersChildrenHaveNoShoes: Jack Malone's job doesn't leave much time for spending time with his daughter, leaving her to her own devices when she gets rejected from MIT. He doesn't even know that she had no safety schools. He spends more time trying to help Teri and her mother after [[spoiler: Mikey dies and Teri starts destroying her house]].
** To be fair, Jack ''does'' try to help Kate at first, before the Litches take up his attention, but his idea of help is discussing Kate's safety schools and she doesn't want to tell him she never applied for any.
* TeethFlying: During the fight with the football players in the school cafeteria, Teri knocks out the defensive tackle's tooth.
* TeenPregnancy: [[spoiler:Teri gave birth to Mikey at the age of sixteen.]]
* [[WhatTheHellHero What The Hell Bully]]: Mitch calls out Teri for stealing Kate's things and using Kate as an emotional punching bag after [[spoiler: Mikey's death]].
** Averted, however, when Mitch finds out that Kate has no safety schools and thus not a guarantee of college in the next year. He doesn't criticize her, and [[CrowningMomentOfHeartwarming rallies her friends at a diner breakfast to help her.]]