Van Argiano serves as the chief scientist for Cinq Flèches, specializing in the study of chiropterans. He led the development of Delta 67 under Solomon's supervision and with assistance from his aide, Archer. Following Solomon's defection, Amshel appointed Van to lead the American branch of Cinq Flèches. Despite being aware of their true nature and objectives, Van chose to align himself with the chiropterans, aiding them in spreading across the globe. Frequently, he is depicted enjoying some form of hard candy.
However, Van was betrayed at the Metropolitan Opera House; he was kept in the dark about plans to transform individuals there into chiropterans. Abandoned by his American contact, Secretary of Defense Grant, to confront the creatures alone, Van was ultimately rescued by David. By the series' conclusion, Van is shown being escorted to trial to answer for his crimes. Additionally, it is revealed that his assistant Archer had been a government-appointed investigator who infiltrated Cinq Flèches to gather evidence.
