The first of the Vesper Holly adventures, The Illyrian Adventure, sends Vesper, along with the faithful Professor Garrett, to the tiny country of Illyria to find information that would vindicate her father's theories about the country's earlier history. Once there, Vesper and the professor are drawn into a struggle between opposing factions and meet the nefarious Dr. Helvitius, who is striving to use the civil unrest to his advantage. Peaceful solutions are reached, but Helvitius escapes. In The El Dorado Adventure, Professor Garrett and Vesper sail to El Dorado to investigate Vesper's large land holdings which someone suddenly and mysteriously wishes to buy. She finds the Chirica Indians threatened with extinction and learns Helvitius is once again behind the scheming. Vesper foils his plans, but he again eludes capture. The Drackenberg Adventure takes Vesper, the professor, and his wife to the diamond jubilee celebration of the...