Hannah is a high school student who moves to Crestmont hoping for a fresh start after experiencing negative rumors in middle school. She enjoys writing poetry, drinking hot chocolate, taking teen magazine surveys, and wearing blue nail polish. Struggling with isolation and the weight of false gossip, she records a set of audio tapes detailing her experiences to share her perspective with those around her before her death by suicide.

Clay is a responsible, academically driven student aiming for valedictorian. He generally avoids parties and trouble, maintaining a pristine reputation at Crestmont High that contrasts sharply with the rumors surrounding Hannah. He works at the local movie theater and harbors an unspoken crush on her, though his shyness keeps him from acting on it.

Tony is a classmate who drives a classic Mustang and prefers older audio technology. He projects a mature, almost parental demeanor compared to his peers. He acts as a steady presence for Clay as the younger boy processes the contents of the tapes.

Justin is an athletic, seemingly average high school basketball player. He catches Hannah's attention when she is new to town, leading to a meeting at the park. His tendency to brag and exaggerate his experiences heavily influences the social dynamics at the school.

Alex transfers to Crestmont around the same time as Hannah and Jessica, initially forming a small support group with them at a local coffee shop. He creates a controversial "Who's Hot / Who's Not" list that circulates around the school, causing friction among his peers.

Jessica is an outgoing and straightforward student who moves to Crestmont at the same time as Hannah. The two girls initially bond over their shared status as newcomers and spend time together at Monet's Café before school gossip complicates their dynamic.

Tyler is a student known for his photography skills, frequently carrying his camera equipment around the school. He has a reputation for being socially awkward, often observing his classmates through a lens rather than interacting directly with them.

Courtney is a popular student who maintains a flawless public reputation. She carefully manages her social image and easily charms her classmates, though her friendly exterior conceals a self-serving approach to high school survival.

Marcus is known as a class clown who often livens up the classroom environment with his jokes. He relies on his humorous persona to manage high school politics and uses a Valentine's Day matching survey to initiate a date at Rosie's Diner.

Zach is a relatively quiet student and a friend of Justin Foley. He participates in a contemporary social topics class with Hannah and attempts to connect with her, struggling to handle rejection appropriately when his efforts are ignored.

Ryan is the editor of the school's "Lost-N-Found Gazette" and a talented writer. He appreciates abstract expression and connects with others over shared poetry notebooks, searching for deep meanings in the written word.

Jenny is a cheerful, sweet-natured cheerleader who actively participates in school fundraisers and social events. She often presents herself as a caring peer, offering rides and support to classmates, though she prioritizes her own protection when faced with trouble.

Bryce is a confident and aggressive student who frequently objectifies his peers. He operates with a sense of entitlement, expecting others to defer to him, and regularly tells those around him to "just relax" during uncomfortable encounters.

Mr. Porter is a professional educator responsible for providing guidance and support to his assigned students. He handles academic and personal advising, though his approach to difficult student conversations relies heavily on standard procedural options rather than proactive intervention.

Skye is Clay's former eighth-grade crush who has since withdrawn from the social scene. She wears baggy clothing, keeps to herself, and spends time riding the bus alone, presenting a sharp contrast to her younger self.

Mrs. Bradley is a high school teacher who handles contemporary social topics. She attempts to foster a safe classroom environment by using anonymous paper bags for positive student affirmations and leads discussions on sensitive mental health subjects.

Ms. Antilly is the guidance counselor who precedes Mr. Porter at Crestmont. She actively tries to help new students acclimate to the school environment by setting them up with assigned "buddies" to foster early friendships.

Clay's mother is a caring parent who pays close attention to her son's behavior. She notices his unusual anxiety and tries to check in on him, offering a stable parental presence while generally trusting him when he asks for space.