Adrianna (Jessica Lowndes) and Navid (Michael Steger) spend their prom night in the delivery room and Brenda (Shannen Doherty) shows up to offer support. Naomi (AnnaLynne McCord) and Liam (Matt Lanter) have revealed their honest feelings for each other and she decides to host an after-prom party at her new house, much to Jen's (guest star Sara Foster, "CSI") disapproval. Showing up late, Naomi searches for Liam but is speechless when she finds him finishing up some business in her bedroom. A furious Naomi confronts and accuses Annie of sleeping with Liam, causing Annie (Shenae Grimes) to finally snap at Naomi and all the party-goers before leaving the party in a rage and doing something that will haunt her for the rest of her life. Dixon (Tristan Wilds) and Ethan (Dustin Milligan) get into a fight when Dixon accuses Ethan of having feelings for Silver (Jessica Stroup). Harry (Rob Estes) and Debbie (Lori Loughlin) chaperone the after-prom party but leave early to lend their support to Adrianna at the hospital, along with Kelly (Jennie Garth).