Turk makes plans to propose to Carla, only to watch all his plans fall apart when one thing after the next prevents him from actually popping the question. Meanwhile, J.D. comforts a patient in need of a heart transplant by explaining his theory about the balance between life and death in the hospital. This theory is put to the ultimate test when a husband must choose between saving his unborn child and his wife's well-being. On another front, Elliot prevents Dr. Kelso from expanding his office space when she launches a campaign demanding that Dr. Kelso build a separate female locker room.