As Penny has her prom dress out after organizing her closet, she, Bernadette and Amy talk about their respective proms, the latter two whose were not what they would have wanted. As such, Bernadette and Amy decide to host a prom night for themselves and their friends, all who accept. Leonard and Penny muse about what their prom would have been like if they knew each other then knowing what they know now. Howard has a problem about who Stuart's bringing as a date, who in turn may cause problems for someone else not at the prom. And Sheldon has an anxiety attack faced with the rituals of prom night, which may include the expectation of coitus.