A cataclysmic event leaves the doctors shaken; Callie, on the verge of a life-changing moment, starts imagining about the hospital and her friends.

Richard tries to get Adele into Derek and Meredith's Alzheimer's trial; Arizona and Mark try to plan a baby shower for Callie; Henry has another medical complication; competition for the chief resident position is amplified.

Meredith's fertility treatments start affecting her eyesight; Mark talks to Callie and Arizona about his role as a father; April learns more about Dr. Stark (Peter MacNicol).

Meredith volunteers to run the ER for a night in hope of proving that she is chief-resident material; Bailey and Eli (Daniel Sunjata) get into mischief; Adele comes to the hospital as a patient.

Meredith and Lexie's father returns to Seattle Grace with stomach pains and a new girlfriend; Alex butts heads with the new OB; Mark bribes Jackson for information on Lexie.

Meredith feels left out when Derek breaks ground on his clinical trial; Bailey's new idea does not go over well with the Chief; Callie irritates her new obstetrician (Rachael Taylor).