Kristin Lindquist

Addison's role as a parent is challenged when Henry's biological mother asks to be involved in his life; Addison's mentor shares a difficult secret.

Veronica gets busted for breaking into the school office. In detention, she's ordered to reorganize the school's files and stumbles on her mother's permanent record. Veronica learns that her mother was suspended for reasons that cause Veronica to further question everything she knows about her mom. Meanwhile, with production of her "Aaron Echolls Story" TV movie underway, Trina Echolls (recurring guest star ALYSON HANNIGAN) returns to direct a Neptune High play and immediately dislikes Logan's new girlfriend, Kendall Casablancas (recurring guest star CHARISMA CARPENTER). Later, Weevil confronts Logan about Felix's murder.

Sarah and Tammy have a big white wedding; ghosts from the past visit both Maura and Ali; Josh and Raquel are unable to hide their big news.

Ben worries that an innocent conversation with Derek could end up causing problems for Bailey; Cristina turns to Shane as tension with Meredith increases; April's upcoming wedding creates an uncomfortable situation for Stephanie and Jackson.

Reno tracks down a rock star who has arranged his own disappearance.

When Ben leaps aboard a 1970s passenger jet as a flight attendant, he must outwit its hijackers before it mysteriously crashes into the Atlantic, and worse, he has to do it all without Ziggy's help.