Robin dismisses Ted's theory of over-correction to explain why Barney is dating Patrice, as she believes he is going through some sort of crisis and she becomes determined to break them up. She sneaks into Barney's apartment in hopes of taking his playbook to show Patrice his womanizing ways but is forced to hide in the closet when Barney and Patrice arrive there. Ted and Lily end up stuck in separate closets in Barney's apartment along with her and they are shocked when Barney sincerely tells Patrice the truth about his playbook and how she has helped him change into a better man. When Robin suggests they stage an intervention for him, the group sets up an intervention for Robin instead. Meanwhile, Marshall and Lily are horrified to learn that Marshall's mother Judy and Lily's father Mickey have been sleeping together.
