S1·E4 Francine's Flashback

When Stan forgets his anniversary, he arranges to have 20 hours of Francine's memory erased, but the CIA temp on duty accidentally erases 20 years. Francine, having reverted to her wild child days, moves into her old apartment with Hayley as a roommate, and ends up going to a festival with Hayley's boyfriend. Meanwhile, Steve asks a good-looking girl out, but needs his wingman, Roger, to "jump on a grenade" for him and date her ugly cousin.