Set in California, the novel begins with a brief glimpse from February, six months prior to the start of the bulk of the narrative. Written from the first-person perspective of Samantha, a junior in a high school and the protagonist of the novel, the opening scene takes place at Samantha’s house as Hailey, Olivia, Alexis, Kaitlyn, and Samantha gather to prepare for their school’s Valentine’s Day fundraiser. The girls form an assembly line to prepare the roses that will accompany the valentines. One person cuts the stem from the rose, another attaches a card, another attaches a ribbon, and so on. With Samantha responsible for cutting the end of the stem from each rose, she is holding scissors when she experiences an unwanted thought, which is a key feature of her OCD:

I grab a rose out of the bucket and pick the scissors up off the floor. The instant I slide my fingers through the handles, this thought hits me out of nowhere, and before I have time to react I feel my brain sink its teeth in and latch on tight, already preparing to fight me for it.