Time Machine/Travel Movie from 80's
I'm trying to find the title of a movie from around the 80's. The plot had an evil guy "rival scientist?" that went back to medieval times to kill off the ancestor of another scientist. The good scientist daughter is sent back with a guy and I think another girl to stop the evil scientist from killing her ancestor. They end up stopping him and they return to the future where the daughter is unhappy and goes back to medieval times to be with her true love. Hope someone remembers this movie and its title.