Well...LUST FOR A VAMPIRE was my least favorite in the Hammer Karnstein Trilogy. I won't take much time with it.
It's plot is a bit messy. Carmilla Karnstein is basically hanging out at a girls school and running through the ladies like a hungry man at a sushi boat restaurant. One man pines away for her love while the other pines away for being a vampire himself.
Girls go missing, man go missing, and cover up operations abound, but I found that I didn't really care about anyone in the film much.
Yutte Stensgaard tosses her Denmark blonde hat onto the Hammer Glamor list and doesn't seem to have a problem baring her...soul...for the role.
Ralph Bates does well as the driven school teacher who wants to be a vampire and the wooden performance of Michael Johnson is fun to watch as he bumbles about. But, the real awesomeness of the film comes from Mike Raven doing his best Christopher Lee impersonation. His booming voice and over the top "I'm a bad man" presence is a joy to watch. It's fun stuff.
Watch LUST for the trilogy aspect, but feel free to do something else while it's playing in the background. :)