Jasmine Warga’s The Shape of Thunder explores the aftermath of a devastating school shooting. The relationship of Cora and Quinn, neighbors and best friends, is strained when Quinn’s older brother, Parker, murders Cora’s older sister, Mabel, at their high school. They rediscover their friendship when Quinn and Cora attempt to time travel to stop the shooting. The Shape of Thunder received a Goodreads Choice Award and was shortlisted for the 2021 Goodreads Best Middle Grade & Children’s Book.

Content warning: The novel contains frequent references to gun violence and suicide. Furthermore, there is a strong implication that the violence depicted in the source material is motivated by racism.

Plot Summary

Cora Hamed celebrates her 12th birthday with her Dad and her grandmother, Grams. Notably absent is her older sister, Mabel, who died in a school shooting the previous year, as well as the person who was once her best friend, Quinn McCauley. Quinn’s older brother, Parker, killed Mabel in the school shooting, as well as two other people before he killed himself. For this reason, Cora and Quinn no longer talk, although both girls feel isolated in their grief and devastated by their respective losses. Quinn leaves a box on Cora’s step for her birthday. When Cora finally opens it, she finds that it contains articles on time travel.

Quinn, isolated and friendless after her brother’s actions, spends most of her time alone in the library. Cora has become closer with her other friends, Mia and Owen, since she no longer spends time with Quinn. Cora reconnects with Quinn at school to discuss the contents of the box. The two girls become united in an attempt to create a wormhole that would allow them to go back in time to stop Parker. Quinn takes Cora to a large oak tree in the woods where she spent time with Parker as a child. Both girls hope that this location, which is personally relevant and charged with memories, will be the perfect location to try to create a wormhole to allow them to access the past. The girls start to spend more time together researching wormholes and trying to time travel. Cora, who loves science, designs an experimental question and hypothesis.

Cora competes in Quiz Bowl, a competitive trivia game, for school. Cora struggles and performs badly at an away game because she is stressed that she doesn’t know where the school’s emergency exits are in case of a shooting. Cora and her friend Mia have an argument. Mia is jealous that Cora is spending time with Quinn again. Meanwhile, Cora grapples with feelings she has for her friend, Owen. She also discusses her Lebanese ethnicity with her Dad and wants to learn more Arabic words and culture.

Quinn and Cora keep meeting up at the tree. They bring possessions from their siblings and imagine the morning of the shooting, hoping that a wormhole will open that will take them there. Cora is frustrated that their attempts to time travel aren’t working and she concludes that they must be missing something. Quinn admits a truth which she has kept hidden: She saw Parker opening her father’s safe where he kept his guns in the weeks before the accident. Quinn sensed that something bad was going to happen but didn’t know what to do about it. Cora is furious with this omission. She stops spending time with Quinn and continues trying to find a wormhole by herself. Cora has a conversation with her Dad about time travel. Cora’s Dad tells her about a conversation he once had with Cora’s mom in which her mother suggested that the key to time travel was understanding the shape of time. Cora’s mother believed time travel was analogous to the shape of thunder, in that it is a difficult concept for our minds to conceptualize and map.

Quinn tries to have a conversation with her mother and then her father about Parker, but neither are willing to engage with her. She feels alone and devastated. Both Quinn and Cora’s families urge them to go to their school’s Fall Fair. Quinn resolves to find Cora because she wants to make amends. Meanwhile, Cora hears thunder from within the school gym where the fair is being held. She excitedly realizes that this is her chance to try to harness the power of the storm to time travel. She runs from the school into the woods toward the big tree. Quinn finds Mia and Owen and asks where Cora is. They tell her that Cora was talking about the shape of thunder and time travel. Quinn realizes that Cora headed into the woods despite the storm, and she follows her.

Quinn catches up with Cora as she is trying to cross a stream filled with water because of the storm. Angrily, Cora tells Quinn that she doesn’t want her help. Cora slips and hits her head, knocking her unconscious. With difficulty, Quinn pulls Cora from the flooded stream and calls for help.

Cora wakes up in the hospital. She discusses her attempts to time travel with her Dad. She is finally hit with the realization that Mabel is dead and that she will never see her again, and she gains a sense of closure. When she returns home, Grams encourages Cora to pack up Mabel’s possessions from their previously shared bedroom. Feeling overwhelmed, Cora calls Quinn and asks her to come over while she’s doing this. Meanwhile, Quinn talks to her parents about the need to talk about Parker; she explains that she has been feeling guilty that she didn’t intervene when she saw Parker opening the safe.

On the anniversary of Parker and Mabel’s deaths, Quinn and Cora go to the tree in the woods. Quinn buries a letter to Parker, where she tells him that she both loves and hates him. Cora plants violet seeds that were Mabel’s favorite flowers.