Part of acting is becoming the character you portray. That includes adopting all of their habits, fears, foibles, and characteristics. Tracy has problems with portraying a submissive woman, and she is sure she is going to lose her job is she doesn't learn fast.
Then her sometime lover, Lindsey, proposes a challenge. Submit to Lindsey's desires and demands for one weekend, and she will learn everything there is to know about being submissive.