Lydia McConnell has a decision to make. She can stay in her safe, sexless marriage, or she can risk everything and commit to her sexually irresistible personal trainer, Blake. The decision should be an easy one, but what kind of personal trainer takes a strap to a client's ass when she disobeys him? At first appalled, she soon finds that she enjoys it. Even needs it. But are Blake's demands on her—24/7 submission and severe spankings for disobedience—too high a price to pay? Lydia is riddled with doubts, and Blake's spurned ex-girlfriend starts causing trouble neither of them needs. Tired of Lydia's wavering, Blake subjects her to a prolonged test of her commitment. The pain, subjugation and punishment she must endure are almost more than she can bear, but she can't break away from his tantalizing sexual control of her. The tension between them continues to mount, and soon her only remaining hope for a life with him is that he grant her one more chance to prove her devotion. But by then, Blake's patience may have finally run out.