Twelve-year-old autistic aspiring Kid Detective Lara Finkel creates FIASCCO (Finkel Investigation Agency Solving Consequential Crimes Only), which her younger sister Caroline talks her into letting her join. Lara hopes to solve exciting mysteries for her classmates. Instead, she finds herself investigating mysteries involving her own family.
The Many Mysteries of the Finkel Family contains examples of:
- "Blackmail" Is Such an Ugly Word: Lara is annoyed when her little brother Benny accuses her of "spying" on people. She prefers "investigating."
- The Bully: On Caroline's first day of middle school, Marissa smashes the zebra Caroline was making out of clay. Caroline's new friend Micah Perkowski tells her that Marissa was just as bad in elementary school, that she made half the kids in fifth grade cry at some point, and that she spread a rumor that Micah peed his pants so everyone would call him Micah Pee.
- Cultural Posturing: Lara's aunt Miriam and cousin Aviva recently came over from Israel and have been staying with the Finkels. Much to Lara's irritation, Aviva keeps talking about how much better everything was in Israel, from the food to the music to the public transportation.
- Eloquent In Her Native Tongue: Aviva was good at writing in Hebrew, but in America she gets bad grades on writing assignments because her English grammar is incredibly poor and she sometimes forgets that she's supposed to write from left to right. Lara admits that her Hebrew is even worse.
- Fantasy-Forbidding Mother: The Finkel siblings' mother nags Lara's older brother Noah to apply to the University of Washington, but he keeps putting it off. Lara discovers that he actually wants to go to community college and become a car mechanic. Lara knows their mother would be furious if she found out.
- Fun with Acronyms: The idea is that when people have a fiasco, they go to FIASCCO. Lara is annoyed that she couldn't come up with an acronym with only one C.
- Jobless Parent Drama: Lara's father has been working for a newspaper for nearly three years. He loved his job, but early in the book he gets fired because his ADHD prevents him from meeting deadlines or completing his paperwork. Lara remembers what happened the last time he lost his job — he didn't play with her for months, mostly stopped cooking, and spent days in his pajamas in front of the TV.
- O.O.C. Is Serious Business: Lara's father is a talented cook. When he cooks a dinner for the family that's almost inedible, Lara and Caroline know something's up. They learn the answer when they sneak into his office and find a piece of paper with the word "severance."
- The Password Is Always "Swordfish": When Lara snoops in her dad's laptop, she easily guesses his password: nlcb777, after his kids' initials. Later, when she breaks into Caroline's phone, she gets the PIN right on the first try because she knows Caroline's favorite numbers.
- Passing Notes in Class: Micah writes notes for Caroline in his notebook. She replies by typing messages in her speech app without hitting "send."
- The Prankster: Micah and his brothers are always playing pranks on each other. He comes up with ideas for pranks on Marissa. Caroline goes along with it partly because she wants revenge and partly because she wants Micah to be her friend.
- Pretentious Pronunciation: Marissa brags about her trip to "Par-ee."
- Proof Dare: When Principal Jenkins accuses Micah of putting a fake dead rat in Marissa's lunch box, Caroline says, "You have no proof that Micah did anything."
- Show Within a Show: Lara's inspiration is the fictional detective Georgia Ketteridge, the protagonist of her favorite book series.
- Silent Treatment: After Lara impulsively reveals everyone's secrets during Rosh Hashanah dinner, her siblings spend the next day ignoring her.
- The Speechless: Caroline is nonspeaking and communicates with a speech app on her tablet. She uses the British setting because it makes her sound more grown up.
- Unwanted Assistance: When Lara is showing Caroline around Pinecone Arts Academy, Caroline tries to talk to a group of kids they meet. One boy says, "Are you really talking to us?" Lara yells at them for being rude to Caroline. Caroline is angry and embarrassed that Lara didn't let her speak for herself and thinks that they definitely won't be her friends now.
- Vengeance Feels Empty: Micah helps Caroline get revenge on Marissa for ruining Caroline's art project by putting fake blood in Marissa's pen, which ruins her art project. Micah thinks it's hilarious, but Caroline feels scared and guilty.
