Sam is a nonbinary autistic teen fascinated by stories of half-lived lives - kids who died before the age of nineteen. When they and their dad move to a new home in Astoria, Oregon, Sam learns that the house hasn't been inhabited since The '80s, when a sixteen-year-old named Billy Clement died of anaphylaxis from a peanut allergy in his bedroom. Sam thinks Billy was murdered, as does their new neighbor, a girl named Shep, and the two of them investigate the thirty-year-old mystery.
The Many Half-Lived Lives of Sam Sylvester contains examples of:
- 20 Minutes into the Past: Billy died in March 1989, which means that the story is set in late 2018 and early 2019.
- 555: Sam and Shep find Billy's obituary, which gives a 555 number to contact his mom.
- Cow Tipping: Referenced. When a kid asks Sam a question about life in Montana, they make a joke about cow tipping to avoid talking about what really happened.
- Dramatic Drop: Shep's mom Esme drops her water glass, shattering it, when Sam tells her that they know she saw Billy die.
- Foreshadowing: Shep borrows her dad's beloved vintage car to drive everyone to the dance, and when they come outside, there's a threat painted on it. They take it to the car wash, expecting the worst, but to their surprise the paint washes off really easily and did no damage to the car. Shep's father is later revealed to be the one who left the message, as he's the killer and he's trying to scare her and Sam away from digging any deeper. He wouldn't graffiti his own car in a way that would ruin it.
- Foster Kid: Sam used to be one before their dad adopted them at age seven.
- Groin Attack: When Carl Wayne tries to strangle Sam to death, Sam escapes by punching him in the crotch.
- Held Back in School: Sam received almost no education while in foster care, and is still a year behind their classmates.
- Homophobic Hate Crime: Sam and their dad left their old home in Montana after Sam was attacked by transphobic classmates who almost strangled them to death with a zip tie on their eighteenth birthday. Both the teachers and the police dismissed it as a prank, and the attackers suffered no consequences.
- Last-Name Basis: Shep's full name is Stephanie Shepard. She hates her first name, and she took her mom's last name after her parents split up.
- Milestone Birthday Angst: Sam worries that they'll become a half-lived life, especially after they were almost killed last year. They feel increasing dread as their nineteenth birthday approaches because they're worried that they won't live to see it.
- No Bisexuals: Invoked. Despite Astoria's more accepting environment, Sky, one of Sam's new friends, has consistently had trouble convincing people he's bisexual. One of the reasons the LGBT club doesn't like Alpha Bitch Blaise is that after he dumped her, she spread it around the school that he's "really" gay, undoing years of progress in about a week.
- Pistol-Whipping: After Sam figures out Carl was the killer, Carl knocks them out with a pistol, then ties them up.
- Self-Harm: Before Sam was adopted, they used to bang their head on the floor. In the present day, they punch themselves in the leg to relieve stress and Sensory Overload. Their dad buys them a punching bag for Christmas so they'll have another outlet.
- The Speechless: When Sam lived in foster care, everyone thought they were nonverbal due to reactive attachment disorder. Their first words after being adopted were "Thank you," spoken on their eighth birthday.
- Time Capsule: Sam's dad finds a capsule in the backyard that was buried in 1987 by Billy and his girlfriend Margarie Frankel, who is now the principal. It contains two cassette tapes, Hot Space and Fame and Fashion, as well as a letter written by both of them talking about their love of Queen and David Bowie.
- Weaponized Allergy: Carl murdered Billy by putting peanut oil on his popcorn ball. He later puts Sam's dad in the hospital by secretly adding walnut extract to the nut-free coffee cake Esme was baking for him.
- What Are Records?: Shep has never heard of cassette tapes before she sees what's inside the time capsule. She says dubiously, "That really plays music?"
- Wrong-Name Outburst: Principal Frankel calls Sam "Billy" several times.
