Sheldon is determined to be proved right when a NASA official comes to school and dismisses one of his scientific suggestions.
Derek's mother arrives in Seattle and meets Meredith for the first time; the patient on death row wants to donate his organs to Bailey's young patient, Jackson; Callie has a patient who had surgery to make him taller, only it caused massive infections in his legs; Owen asks Cristina out on a date.
Jim backs out of having a vasectomy but is unable to admit he could not go through with it to Cheryl.
Larry relishes his role as a "social assassin" until it becomes a liability with his friends, on the golf course and at a Palestinian restaurant.
Sheldon wants to experiment on Howard's kids.