Best friends Allie Gator and Amy Gator are determined to win the costume contest at the Swamp Street Halloween parade. But what can they wear for their prize-winning costumes? Should they be ketchup and mustard? A pencil and an eraser? They are stumped -- but they had better think of something great before rival gators Marvin and Dave run off with the prize!Soon another project catches their eye -- they see a poster featuring a lost pet lizard named Louie. The Gator Girls make up their minds to find Louie...but can they find him and make it to the contest in time?In "Gator Halloween, the fourth book about the irrepressible Gator Girls, authors Stephanie Calmenson and Joanna Cole and illustrator Lynn Munsinger capture all the highspirited excitement of Halloween. Fans of the previous books in the series and those meeting Allie and Amy for the first time will find tricks and treats in store!