Chapter 90 of All the Colors of the Dark portrays Saint as she devotes her weekends to working at the public library in Panora. She approaches her tasks with a quiet grace, much like a swan gliding effortlessly over water. While managing the usual library duties—handling inquiries, checking out books, and maintaining the outdated card catalog—Saint finds quiet moments to focus on a personal mission: researching a girl who appears in a painting. This pursuit becomes a central part of her routine, and she carefully sifts through records and documents, hoping to uncover more about the mysterious girl. Each day spent at the library offers a blend of routine tasks and the thrill of uncovering potential leads, as Saint grows increasingly absorbed in her investigation. The setting of the library becomes a symbol of Saint’s dedication and determination to solve the mystery, even if it means spending long hours in isolation, away from the more typical teenage distractions.

Saint’s commitment to solving the mystery takes a more active form as she reaches out to coroners and hospital receptionists across several districts, all in search of information related to the girl in the painting. Despite her own self-doubts and the protests from her grandmother, who expresses concerns about the feasibility of the investigation, Saint continues to pursue the inquiry. During a casual moment shared with her friend Norma over lemon muffins at a café, Norma voices her skepticism, stating, “He can’t know what she looks like,” suggesting that the person Saint is searching for may not even exist in the way she believes. However, Saint is undeterred, and as she watches Patch embrace Misty at the bus stop, she becomes more convinced that there is a connection between the painting and the missing girl. Her resolve strengthens, and she remains determined to uncover the truth, even as others question the direction of her investigation. This inner turmoil and external skepticism create a powerful tension, pushing Saint to confront both her doubts and the overwhelming need to find closure.

Throughout the next year, Saint’s dedication to the search becomes more focused and methodical. She learns that Patch is also involved in tracking down the parents of missing teens, taking meticulous notes during his morning rides. Meanwhile, Saint continues her exhaustive search, focusing particularly on public and state records, and spending considerable time poring over death certificates. She begins to question if Grace, the girl in the painting, may be older than she initially thought, expanding her search parameters to include those who might have been overlooked. The toll of her relentless efforts becomes evident, as Saint makes nearly three hundred calls to the confused relatives of potential matches, each conversation bringing her closer to an answer. She changes her approach, leading with the question, “Do you know a boy named Patch?” in hopes of uncovering any connections that might link back to him. Despite facing dead ends and unreturned calls, she persists, driven by an unshakable need to uncover the truth, even if it means confronting uncomfortable possibilities along the way.

Saint considers widening her search further, even contemplating the idea of accessing federal records, but the absence of a last name complicates her efforts. After a year of watching Dr. Tooms, she begins to lose interest, becoming convinced that he holds no answers about Grace. Patch, in the meantime, continues to contact her at strange hours, leaving cassette tapes filled with his frantic thoughts and vivid memories of Grace. His recollections are filled with sensory details, such as Grace’s scent, which reminds him of lemon and peppermint, along with memories of a particular place near Baldy Point. These tapes, while disorganized and rambling, reflect Patch’s emotional connection to Grace, and Saint finds herself caught between his unresolved feelings and her own search for answers. The tapes act as a bridge between the past and present, keeping the memory of Grace alive for both Patch and Saint, even as Saint questions the direction of her own life.

Amidst the emotional chaos, Saint continues to excel in school, distancing herself from the social excitement of prom and college discussions. She chooses a simpler appearance, tying back her long hair and adopting a more understated style, signaling her desire to withdraw from the typical teenage distractions. However, she cannot completely escape the pull of the world around her, as she receives a momentary distraction in the form of roses delivered by Jimmy Walters, who invites her to prom. The gesture forces Saint to confront her emotions, particularly her conflicted feelings about Patch. Her grandmother, Norma, encourages her to consider Jimmy’s invitation, subtly reminding her that Patch has been rumored to be going to prom with Misty. This creates an emotional tug-of-war within Saint as she contemplates her memories of Patch while also considering the fresh possibilities that Jimmy represents. The invitation serves as a symbol of the new experiences waiting for her, but the past still lingers, complicating her decision and showcasing her internal struggle between moving on and holding onto the past. This chapter is a turning point for Saint, highlighting the emotional complexity of growing up and the tough choices that come with navigating relationships, personal growth, and unresolved histories.