Private detective Elvis Cole is hired by Meryl Lawrence to help find a woman named Amy Breslyn, who has disappeared with almost a half a million dollars of their employer's money. Amy's son Jacob, a journalist, died in a terrorist bombing in Nigeria about a year ago. Since then, Amy, a chemical engineer, has been different. As Cole is working on the case, he crosses paths with cop Scott James and his dog, Maggie, plus the rest of the LAPD. The police are very interested in what Cole is doing and are having him followed. Scott, himself, is in danger, because he can ID someone wanted by the authorities that has a connection to Amy and is probably involved in bomb-making. Cole and Scott secretly team up because they realize that, by sharing information with each other, they might be able to get the results they need. The Promise, at first, takes a bit of time to set up the plot, but soon Crais' series characters Cole, Scott, Maggie, Joe Pike, and even Jon Stone move to the forefront and the reader is treated to another great read.