After witnessing some strange behavior from Bridget and Kerry, Cate tries to find out what they are up to. Meanwhile, C.J. and Rory doubt Jim's ability to put an engine back together after he falls in love with a classic car.

After turning down Bridget's request to throw an after-prom party in a hotel room, Cate decides to throw a school- sanctioned party at the house which totally embarrasses her kids. Meanwhile, Kerry tries to make a political statement by inviting a girl to the prom, and Rory is overjoyed when a hot senior asks him to the dance.