The novels were originally published in 1980, and it shows (in a good way). So far, I have only read the first one (The Demon Count). It is an obvious homage to gothic novels. Like Jane Eyre, it is told in first person. Unlike many recent first person new adult romances, there is only one narrator, so we only get the heroine's point of view. The eponymous count remains a figure of mystery for most of the novel. Is he an evil murderer? A spy? A vampire, as the superstitious locals believe?
Like many old school historical romances, it contains an emotionally-distant older hero who is frequently patronizing and occasionally abusive toward the heroine. There is much melodrama, described with many adjectives. The setting is exotic. The heroine had a toxic mother, and the hero had a toxic wife (now deceased). Unlike most old school romances, however, the heroine is rather savvy and cynical (except when she is occasionally naïve and trusting).
I did not get the impression that Anne Stuart actually visited Venice before writing the book. There is an obligatory visit to Florian's, and a reference to some other characters going to Torcello for a picnic, but there is a dearth of detail about those places. Joanna Shupe used both of those settings in The Courtesan Duchess and made me feel like she had been there. The descriptions of Venice in The Demon Count could have come from any guidebook (or a great many movies).
Still, I loved the general atmosphere, and I have sufficient memories (and vacation photos) of my own to imagine in vivid detail the canals, campos and crumbling palazzos that Charlotte Morrow encountered in Venice.