Derek finds Meredith in her tub, completely under the water, and pulls her out. She tells him she doesn't need rescuing. But he knows she's melancholy after the hurtful things her mother said to her when she was lucid and is afraid she was trying to drown herself. Meredith asks Izzie why she can't just believe in "happily ever after" and Izzie says she doesn't know what to believe in herself anymore.
Burke, Mark and Derek are amused to see that the Chief has dyed his hair now that he's single again. Addison comes to his defense and tells them all to leave him be, then confesses that she dyed her hair blonde after Derek left her the first time.
Burke wonders why Cristina hasn't told her friends yet about their engagement and she says she'll do it today. But she makes him promise to let her tell Meredith first. Meredith is no mood to hear any good news, however, so Cristina doesn't say anything.
Derek confides his frustration with Meredith's depression to Burke, so Burke tells him about his engagement. He doesn't plan on Mark overhearing their conversation. Mark immediately tells the Chief, who congratulates Cristina. She is upset with Burke, but he tells her she had ample time to tell Meredith, so why didn't she?
Meanwhile, Callie feels that George isn't respecting her position as his boss now that they're married and reminds him that at work she's his boss, not his wife.
The residents are doing triage drills led by the annoyingly perky resident Sydney when the Chief announces that he needs all hands on deck: There's been a multiple victim accident. Alex, Izzie, George, Meredith and Miranda head out to the scene, a ferry that ran into a container ship because of fog. There are bodies everywhere and the ferry itself is on fire. Miranda tells the interns they're on their own, and sends them into the fray.
George helps a woman with a serious stomach injury who makes him promise to find her 7 year old son before she lets him take her to Seattle Grace. He's unable to locate her son before she has to go into surgery but even though she begs them to wait, they can't wait any longer.
Alex rescues a pregnant woman who was crushed under a huge pylon. Her face is hideously swollen but, miraculously, her baby is still alive. He wants to continue with the case at the hospital and make sure the baby will be okay, but the Chief hands the case off to Cristina.
Cristina is not happy when Burke doesn't want her to scrub in on the pregnant woman from the accident, but instead asks her to check on his existing patients. So neither Cristina or Alex end up doing the surgery, but Alex goes to reassure the woman that she's survived so far and he expects her to still be alive after the surgery. Addison finds him and tells him he did good today. He goes to the waiting room to tell the victim's families their status, but is overwhelmed by their desperate demands for updates on their loved ones.
At the accident site, a man begs Izzie to come help his friend, who is trapped under a car on the ferry. When she gets there, she realizes she can't do much to help the man, whose injuries are massive, and that they need Search and Rescue to get him out. But she stays and tends to him as best she can and sends one of his friends to get the Search and Rescue team. After a long delay, the friend comes back alone. Search and Rescue isn't coming they have 15 more cases they need to get to first. The man goes limp and then starts to seize violently. His friends tell Cristina she has to save him.
A lost little girl attaches herself to Meredith, refusing to go with anyone else. Meredith is working on a man with a bad leg injury who's lying at the edge of the dock, away from everyone else. She calls for help, but no one will come to her aid, so she has to ask the girl to help her get some equipment out of her bag. The girl won't talk and Meredith says when bad things happen she doesn't talk either.
The man suddenly says he can't stand the pain and starts to flail wildly, knocking Meredith into the water! No one else sees what's happened and the girl just walks quietly away. In the water, there is no sign of Meredith.