S6·E18 An Affair Not to Remember

Caitlin takes a trip down memory lane and realizes that she and Charlie met years before and that he was the reason why she lost what might have been the best relationship of her life. Flashback to a preppy and conservative Caitlin and a cool, life-of-the-party Charlie at an old college bash. The flashback makes Caitlin realize that her current boyfriend, Tom, might not be right for her, and she ends up kissing Charlie! Meanwhile, the Mayor bartends at a fundraiser at which Paul is trying to pick up a woman, and the woman's friend has fallen for Carter, who is gay.