Homicide detective Michael Britten (Brotherhood's Jason Isaacs) seems to be getting accustomed to the two realities between which he has been dividing his time since the car accident. In the ''red'' reality, his teenage son died in the crash and his wife survived; in the ''green'' reality, his wife died and his son survived. In the green reality tonight, Britten's psychiatrist (Cherry Jones) is enthusiastic about this strange split, seeing it as a wonderful coping mechanism that can help Britten solve crimes in his day job. But in the red reality, his other psychiatrist (B.D. Wong) sees it as a real problem. Tonight, once again, the two realities bleed into each other. In one reality, Britten is investigating the murder of a doctor; in the other, the murder of a homeless man. Both men have the same name, and clues in one case might help solve the other. We also learn that Britten's boss (ER's Laura Innes) might have had something to do with the crash.