University professor Vera, trapped in a cold, loveless marriage, spends her nights succumbing to the commands of an anonymous online user, S. When transfer student Solène appears, Vera is astonished to realize that she is S, the anonymous online user who dominates her. Caught between her husband Joyce's psychological abuse and Solène's forceful and dangerous possessiveness, Vera struggles agonizingly between morality and desire. They develop a secret master-pet relationship, and when Joyce stumbles upon their secret, he blackmails them. Solène orchestrates a scheme that accidentally cripples Joyce, and eventually uses a major fire to completely eliminate the obstacle. Freed from the shackles of marriage, Vera completely succumbs, and she and Solène remain together in their forbidden desires.
