Shannon and David are pushed to new limits as they finish up the last day of their couples retreat.  Meanwhile, having returned from Puerto Vallarta, Vicki throws a Fiesta party where a piñata isn't the only thing that's bashed. At the party, when Heather introduces her friend Meghan to the group, Shannon realizes that she has a history with Meghan. Plus, Vicki and Tamra's shaky friendship becomes even more complicated as the two come face-to-face after having avoided each other for the past six months.

A trip to Napa concludes with tensions at a high. Back in the OC, Vicki and Brooks consider some unconventional cancer treatments, Meghan puts the final touches on her first OC charity event while Heather faces the harsh reality of going over budget on her dream home. Meanwhile, Shannon receives some shocking news and unresolved issues between her and Meghan become the topic of the ladies' scrutiny at Meghan's JDRF charity event.