The following are a few things I've wanted to try.
A girl who is either kidnapped or sold into slavery of a fashion. Her owner, of course, would be harsh and critical until he fell for her and became very tender and loving toward her at which time she would be confused and he would have to gently lead her out of her shell. Similarly, it would be another interesting plot for a character I played to have been trained as some sort of sexual toy for lack of a better term, to where she adores her master who is similar until his reaction is similar to that I just listed.
Two James Bond- or Alias-types from different organizations forced to work together, at first hating each other, etc.
Being rescued from and subsequently escaping (depending on setting) a dungeon, research facility, prison, etc.
Accidently rescuing a guy from a similar such thing as listed just above (preferable modern so I could have cool guns