Cameron is in charge of the school's big spring dance, but when a popular teacher returns from sabbatical, a bit of not-so-friendly competition blooms. And with Claire on chaperone duty at the dance, Phil gets Haley to accompany him to his annual realtor's banquet and is looking forward to impressing his little girl. Elsewhere, Mitch starts a new job and can't seem to get a good read on the new boss or the work environment. Jay and Gloria babysit Lily and an accident with Gloria's purse ignites a case of whodunit and it's Lily's word against baby Joe's.