Catherine is experiencing hallucinations and refuses Dr. Hartramph's urging to be admitted into a hospital. Her behavior is becoming increasingly manic and it isn't long before Mahmoud begins to piece together what she's seeing. Meanwhile, Bickman is reluctant to go back into the operating room after Joey's botched surgery. Catherine encourages Bickman to see Lina so that she can re-wire his brain. A woman confronts a knife-wielding man on the street and the team wonders if it's really a display of bravery or if she has an absence of fear.