I guess that's a long shot...but I'd like a line based on threading, here's the rough idea to it...
They met randomly in a cafe or the supermarket or even a bar. They spend the night together and the only thing he knows about her is her first name. When a few days later he starts a new job he is shocked to discover that the woman he spent the night with is either his boss' wife or his new boss...details can be worked out. I would be playing the female in this!