Charlie breaks all the professional rules by starting a friends-with-benefits relationship with a hot woman subject from the sex study. Also, Nolan and Patrick fight over a woman.
Charlie's trip with the group is interrupted when he gets some interesting news from Kate. Also, Charlie's house is unwittingly used for a porno shoot.
Charlie has to deal with the aftermath when his dad moves in with his patient Ed and they hit someone with their car. Also, Lacey takes Nolan out for a night of clubbing.
Charlie goes too far when he gets jealous of Jennifer's much younger boyfriend, Canvas. Meanwhile, Patrick helps Lacey look sexy for her first modeling gig.
Charlie tries to stop Kate from having sex with the executive in charge of funding their study; Charlie's dad tries to stop Lacey from throwing herself at a sleazy yoga instructor.
Charlie invites Ellie (Brea Grant), an attractive grad-student, to observe a therapy session only to have to compete with Nolan for her affection. Meanwhile, Ed and Martin come up with a plan to scam the government by hosting a disabled war veteran in their house.
Charlie accepts a new patient, a pimp named Ray James II, into his therapy group. After Charlie sleeps with a young woman called Sasha (Anna Hutchison) who approached him at the bar, she reveals that she's a hooker and that Ray sent her as payment for his sessions. Meanwhile, Lacey, Nolan and Ed are creeped out by Ray, and attempt to hold their own self-help session without Charlie present.
Charlie invites a new therapy patient named Bob (Bob Clendenin) into the group, who casually tells everyone that he is the devil. Nolan makes a deal with Bob to sell his soul in exchange for Lacey falling in love with him. When Lacey is all over Nolan at the next session, even the skeptical Charlie starts to wonder. Meanwhile, Jen falls for a new neighbor while Sam falls for a young man who appears to be the neighbor's son, but the two are later revealed to be gay.
Charlie asks for a second chance with the woman to whom he lost his virginity, and Lacey and Patrick try to keep up appearances when Lacey's parents pay a surprise visit.
Jordan's twin sister, identical in every way except hair color and the addition of fake boobs, is in town. Jordan tells Charlie that the two don't get along ever since her sister slept with her former fiancee. She asks Charlie to help mend the damage between them, but he winds up sleeping with the twin. Elsewhere, Lacey's sister blackmails her into buying her whatever she wants in exchange for not revealing to their parents that the marriage to Patrick is a sham.
When Charlie breaks it off with a police officer he's been dating, she abuses her power to make his life miserable. Meanwhile, Jordan struggles to establish a casual sex relationship with Sean.
When Charlie tricks Lacey into believing her father is broke, she gets engaged to an obnoxious billionaire. Meanwhile Nolan makes a business arrangement with Sean's strip club.
Charlie wants to make a business deal with Jordan's ex-husband, but he knows Jordan won't go along if she knows the identity of the business partner. Meanwhile, Lacey gets jealous when Nolan tries to save a family of birds.
