Ten-year-old Casey is a resentful new resident of Siesta Key in Florida where her mom and dad are taking over as manager and handyman of a condo complex. She makes friends with a boy named Matt and an elderly gentleman, Mr. Kearns. Both of them will introduce her to the joys and hazards of Florida living. Matt and Casey are upset when Mr. Kearns is accused of stealing from one of the condo residents. They are sure he is innocent and want to solve the mystery of the stolen money. Casey learns a great deal about Florida and human nature as her new life begins.