Ten-year-old Louis Daniel hates it when Mama treats him like a baby. But when Hurricane Katrina blows through the Gulf Coast on a fateful August night, followed by broken levees and rising floodwaters threatening New Orleans, Louis feels like a little kid again. With no time to gather their belongings save Louis's beloved horn Daddy leads the family from their home and into an unfamiliar, watery world of floating debris, lurking critters, a winsome black-and-white dog, and desperate neighbors heading for dry ground. Taking shelter in the already-crowded Superdome, Louis and his parents wait and wait. As the days pass, the electricity goes out, the air conditioning dies, the bathrooms are closed, and people around them begin to bicker as they run out of food and water. When Daddy fails to return from a scouting mission within the Dome, Louis knows he's no longer a baby. It's up to him to find Daddy, with the help of his prized cornet.