CONDEMNED TO LIVE (1935) (http://imdb.com/title/tt0026230/) - This is the type of film that you can not read the cover before watching the movie. Otherwise it won't be as interesting. If you find a copy just watch it without getting the storyline first. Won't tell you much but a pregnant woman gets bit by a vampire bat in a great scene were three people are trapped in a cave by natives in Africa. You have to see this bat attack this woman. Great stuff. Great Universal type sets and angry mobs with torches. It's worth viewing just for that.
(http://www.missinglinkclassichorror.co.uk/demned2.jpg)