A recent idea I had, inspired somewhat by the family in Traffic...
In a major metropolitan area, a local politician/district attorney has been putting the pressure on local drug dealers. One drug dealer finds out her has a teenage daughter with a few bad habits of her own. He decides to kidnap her from a club but not for ransom. Instead he plans to abuse her while getting her hooked on harder drugs. As she becomes more dependent on him, things get more degrading. They frequently occur in public area and are video taped to be sent to her father and posted online. Needless to say the father is frantic to find his daughter, if not out of genuine concern for her safety then at least for his career.
This one I'd like to get really extreme, so if you're a sick freak I'd love to hear from you.