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.

The new "evolved" Charlie has to deal with a ghost from his old carousing, baseball-playing days when a unattractive woman he slept with just to break a batting slump shows up as a new patient in group therapy.

Charlie's plan backfires when he attempts to remedy his group with sleep-deprivation therapy.

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

Charlie falls for Jen's hot new business partner, Lori - played by Charlie's real-life ex, Denise Richards - only to find she thinks therapy is a scam. In the therapy group, Patrick asks Charlie to counsel the angry ghost of his mother, who he believes is haunting his apartment.

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.

Charlie has to evaluate the depth of his involvement in his patient's lives when he accidentally helps his patient who vicariously enjoys other people's anger hook up with a crazy woman.

Charlie gets an unexpected visit from his hyper-critical, bullying father. In the therapy group, Charlie attempts to help Lacey with road rage.

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.