Shep, Callie, and the other dogs leave the animal shelter and meet up with Honey and Fuzz, a cat who can speak dog! Shep decides to let Fuzz into their pack because of Honey's attachment to him. The pack doesn't have a safe space to sleep, and when they finally find an abandoned boat, fights break out because of the crowded circumstances. There are problems with wild dogs as well as alligators, but Shep does meet the fierce Blaze, a girl dog to whom he takes a shine. Every day is a struggle, because food is scarce and pack politics are complicated. At one point, Shep decides to throw Fuzz out of the pack, with disastrous consequences. Just as Shep is beginning to get his pack to a point where they have food, shelter, and can get along with each other, humans start arriving back in the city and kidnapping dogs.
Like the Warriors books, this series focuses on the survival of animals who have to deal with both each other and the privations of their environment. I was able to tell the dogs apart much more easily than I could tell the cats apart, and the exterior crisis of the flood (basically something like Hurricane Katrina) makes the survival seem more realistic.