S6, E4: Dr Cox channels TV doctor `House' to solve three medical mysteries, including: why a man's skin is inexplicably orange, why a young woman with no coronary issues has a failing heart, and why Eliot is taking her anger towards Dr Kelso out on Turk. However, the doctor may be missing the biggest clue of all when Carla begins to show signs of postnatal depression. Meanwhile, JD tries to be the best boyfriend ever.