At night, Drew calls a house meeting and lays down the ground rules - no masturbation, no seductive behavior, and of course, no sex. For Kendra adapting to rehab is proving to be difficult. Now almost a full day without her husband, Kendra breaks down and wonders if she's going to be able to make it. After only a day in rehab, Kendra and the rest of the sex addicts are extraordinarily fragile and emotional. They are about to take on one of the toughest experiences of their lives and it's anyone guess if they can make it through 21 days of intense treatment without their drug of choice: sex.

As treatment begins, Dr. Drew and Jill ask the patients about their backgrounds, learning about the patients' emotional, physical or sexual abuse, which is typical of sex addicts. Phil finds himself attracted to Amber. Dr. Drew observes that Kari Ann is resistant to treatment and the restrictions imposed on her, demanding to be allowed to go home, and having angry exchanges with Dr. Drew's staff. Dr. Drew suspects that she may be suffering from drug withdrawal, and is determined to keep her at the clinic until he can determine this. He also wonders if her erratic behavior is do to a psychiatric problem, but she walks out of the interview that Drew arranges with her and a staff psychiatrist.

Four days into treatment, the patients are becoming increasingly agitated, with the patients, Kendra in particular, annoyed at Kari Ann's refusal to awaken and participate in group sessions with the others, and their perception of the preferential treatment given to her. Drew and Jill have the women remove their makeup in order to experience their "true selves", but Kari Ann refuses to participate. Kendra, Nicole and Amber each have one-on-one sessions with Dr. Drew and Jill. Kari Ann writes an angry letter to Kendra, but Kendra returns it to her, explaining that it seems better suited as a letter for her. Feeling the others are against her, an emotional Kari Ann asks to speak with the staff.

During a morning group session Jenifer refers to herself as "a nutcase" and "loony tunes" stating that she has "failed miserably" from acting out in her dreams when she is asleep with other members of the program. Dr. Drew and therapist Jill assure her that these are symptoms of withdrawal which occur after approximately 1 week of going without sex. In a private one-on-one session with Jill in her room Kendra explains that she is uncomfortable expressing herself in group as long as Kari-Ann is there.

Well into the treatment process, the patients are having a difficult time as they are finally taking a look at their lives and how they have affected the ones they love. Because the women have all been sexually abused or raped, and have never really dealt with the emotions involved, Drew sends them to Children of the Night, where they design t-shirts showing what they've gone through. Later, Drew has Duncan see Dr. Sealey to start exploring his issues with men. Drew and Jill meet with Kari Ann to get a little deeper into her past abuse. Jenny reveals to Kendra and Duncan that James told her he wants to "rape the s***" out of her. The next morning at group, emotions run high as the subject is brought up.

Two weeks into rehab, Kari Ann is still having trouble with the most basic aspects of treatment, like getting up on time. And James has become the outcast after making a remark, supposedly in jest, that he wanted to "rape the s***" out of Jenny. Despite Selma's efforts, Kari Ann doesn't get ready in time for group, but those who do are introduced to the concept of "The Circle Plan" - a system for ranking behaviors from safe and healthy, to potentially risky for their sobriety. The next morning Phil learns that his grandmother has died, raising unresolved issues about the untimely death of his mother eleven years ago. Drew agrees to arrange a therapy session for Phil and his father.

As rehab nears the 21-day mark, it seems that Kari Ann is still not with the program. When Shelly wakes her up for group Kari Ann turns over and promptly goes back to sleep, breaking yet another rehab rule. During group Dr. Drew directs the patients to look forward to life outside rehab. Penny discusses the possibility of leaving porn, and Amber shares her guilt over her father's death with the group. Kendra, anxious about leaving rehab, confesses that she feels like she's barely started the work and is basically at the point where she's cut open an artery and all she has is a band-aid. Drew and Jill assure her that rehab was just the beginning of a long journey.

The group looks back on their progress and head to group therapy in a cheerful mood. Dr. Drew informs them that they'll be offering them continuing treatment with Jill, a very intense program. He tells them to think about it, asking for a decision at graduation. While group goes on, James has headed off for surgery, to remove the STD-caused cancerous growth on his throat. The patients are grateful for what they've learned in rehab, but trepidatious about returning to their old lives, and not sure if they want to make the incredible commitment that the program with Jill requires. Finally, graduation arrives.