Meredith grows increasingly dissatisfied with fact that she knows nothing about Derek's life. Meanwhile, Alex treats a patient whose religious beliefs jeopardize her chances for recovery, and Izzie contemplates reconnecting with her estranged mother. Also, a pregnant woman in her 40s who's been diagnosed with cancer disagrees with Cristina's medical advice. And the interns are mystified by a patient who's being treated for seizures and who thinks he's psychic.