When Stephanie St. James, AKA Miss Prim and Proper, agrees to accompany sexy FBI Agent Kase Mayeux to a wedding, she expects little more than to dance the night away under the Louisiana stars. But, Sinful being what it is, she soon finds herself embroiled in an undercover search for drug traffickers, as well as acting as an etiquette coach for Swamp Team Three. When a member of the wedding party is murdered, and Ida Belle and Walter disappear, Stephanie and Kase join Fortune and Gertie in a race to find the killer before the list of victims grows.