I've been quiet for far too long, so I'm floating a couple of ideas. Both are fairly adaptable, so if you let me know what your particular requirements are I'm sure they can be incorporated in either.
You know the tale: the Illuminati are a bunch of all-powerful individuals pulling the stings of the world's governments, banks and big businesses. It's an annoyingly-persistent urban myth, right? Wrong, actually. They very much exist, and are seeking to expand their influence. As part of their drive to expand, they are looking to recruit a select number of individuals and to bring them around to their way of thinking. Their modus operandi is to offer residential courses, attendance of which guarantees a fast-track to a glittering career in some of the world's most prestigious organisations, in exchange for indoctrination with their ideals. Their courses are run at a number of venues worldwide, and one such centre is Upper Meads Academy, an institution aimed specifically at women and located deep in the English countryside. My character is Dr Stefan Krask, trained as a psychiatrist but now Dean of the academy. Your character is a married woman in her mid-30s to early 40s (it's up to you to fill in the details) whose husband has recommended you attend. Of course, once enrolled you discover how extreme is the corruption of absolute power. (N/C, medical, sub/dom)
This one is a husband and wife scenario. Your character is similar to the above. You have been caught by your husband engaged in a fairly innocent online relationship with another man. Desperate to keep your marriage alive, you offer to make amends, and ask how you can do so. He tells you that he fully intends you to pay for your indiscretion, but that you will know what the penalty is to be at the time of payment. (kidnapping, N/C)
Granted, neither is what you'd call burningly original, but I'm a firm believer in the adage that 'it's the way you tell 'em!'