I'm looking for an old tv show or movie, I think in black and white, possibly post-apocalyptic. Throughout the story someone might be a vampire, but we are not sure. In the end we see the man and woman driving away in their car, and the woman is about to bite the man, indicating that she actually was turned to a vampire. I think there was also a doctor with a strange-sounding name (especially for an 11-year old non-native English speaking boy) possibly starting with a Z or something like that, who may be the main villain/vampire.
I hope someone knows which show or movie this is from. I've been looking for it for so many years now.
