I literally just got an idea. It's my destiny to try that idea. I owe it to the universe. Or ... well, something.
Anyway. Here is the idea.
It can work in any setting, but I lean toward modern. It involves a man of a fairly eccentric character ( you'll see! ) enlisting the services of a highly skilled ( and attractive ) assassin. Insisting the job is far too important for him to leave in the hands of the assassin, the two work together, trying to track down the target. Somehow, their target manages to always stay one step ahead, outsmarting them at every turn. Over time, a relationship of sorts develops between the assassin and the employer. The twist, if you hadn't already guessed, is this: the employer and the target are the same person. To clarify, it's not a case of a split personality or the employer being misled somehow. It's him deliberately putting a price on his own head for the sake of getting to the assassin.
I'm not aiming for anything serious, per se. I'd prefer something more light-hearted and humorous ( though not outright comedy ).