Charlie - a baseball player with anger issues turned anger management therapist - decides to return to therapy after a bad run-in with his ex-wife's new boyfriend. The only problem is he just happens to be sleeping with the one therapist he trusts: his best friend, Kate.

Kate steals a patient from Charlie, fueling the competitive rivalry between the two therapists.

Charlie and his ex, Jennifer, are having an issue with how Charlie still tries to manage her life when Cleo - one of Charlie's patients from his prison anger therapy group - shows up on his doorstep, fresh out on parole. Jennifer decides to get back at Charlie by dating the ex-con.

After Charlie and Kate have sex, he innocently asks her if she wants to go to a movie. Kate interprets this as a romantic gesture, rushes to fix him up on a date the next day with someone else and the two are forced to exam the nature of their odd relationship. At home, Sam kisses a girl at school and a picture of it ends up on Facebook.

Charlie lets his father help him coach a high school baseball team with bad results.

Charlie and Kate try to control their sexual urges as they begin work together on their sex study; Lacey starts a new job as a pharmaceutical rep.

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 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.