Nach den schockierenden Enthüllungen des vergangenen Falls sind Mason, Olivia, Randy und Danielle davon überzeugt, dass nur eine Lösung des Falls "Marietta King" ihr aller Leben retten kann.
Prince Paul, still attending the same boarding school as Jack and Mike Arnold, invites them and their sisters, Peggy and Nora, to his palace in Baronia for the holidays; but it is so hot there in the roasting summer that the entire royal household adjourns to their castle up in the mountains.