The book contains 39 chapters; each is short and easy to read. This helps increase the pace and gives the novel a page-turner feel: Readers will be tempted to read “just one more chapter,” and the book will seem to race along. Toward the end of the book, the chapters get shorter, which increases the sense of hurtling speed and an onrushing emergency.

Except for the first one, all chapters are titled with time stamps like “07:45AM,” which adds a note of urgency and tension to the novel’s flow. It suggests that the clock is ticking on the approaching storm, that things can happen in a hurry, and that every minute counts. The precise times also reflect Chase and John’s obsession with precision, especially in an emergency. Some chapters are only minutes apart, switching back and forth quickly between Chase’s group and John’s team as they converge on the same area. (The technique of titling chapters by sequential moments also appears in the popular middle grade novel about the American Revolutionary War, The Fighting Ground. A study guide for that book is available at SuperSummary.com.)