On Mother's Day weekend, Clare still grieves over her long-dead mother and Steve cannot figure out how to increase her spirits. Kelly must share a shocking secret with Brandon when she thinks that she may be pregnant. Meanwhile, Valerie makes a pass at David as part of her latest scheme to get him to buy her share of the Peach Pit After Dark as part of her nefarious plan to invest the cash in Kelly's father's business. Donna becomes stressed out from balancing time with David and studying for her final exams, and has another run-in with her cold-hearted business professor, Langley, who openly disapproves of Donna dating David because the professor sees him as a distraction to Donna's future.

Steve goes crazy on a Year 2000 "Y2K" millennium planning, ignoring or avoiding planning a holiday trip with Janet. Noah becomes openly hostile to Matt after he is hired to sue Noah's late father's oil company for environmental pollution in a class action suit. Meanwhile, Katie returns to David and wants to move forward with him, without sex. While babysitting her half-sister, Erin, in her mother's apartment, a hidden camera catches Kelly and Matt having sex in which, as a result of circumstances, ends up in Gina and Dylan's hands. Wayne, a fashion model, makes a play for Donna while Noah pressures her to keep her distance to the guy. Also, Dylan and Kelly deal with the fallout after their fling in Mexico is found out by Gina.