An erratic driver approaches them rapidly from behind, swerving to pass around them, as the car continues to weave across both lanes of the road until it hits the hillside and rolls over. The doctors pull over, and Sam tells Maria to call the highway patrol on their handy CB unit, while he grabs his kit and heads over to the scene of the accident.
The driver is squirming in his seat, and Sam cautions him not to move, explaining that he's a doctor. The man says he's okay and explains that he was driving so poorly because his brakes went out. Maria arrives with her stethoscope at the ready, and the man becomes combative when he sees it.
He forces his way out of the car and grapples with Sam, while Maria grabs him from behind, trying to pull him off.
He throws her off and picks up a rock and bashes Sam's skull in with it. Sam is unconscious on the hood of the car, and Maria is left facing the attacker.
He goes after her, but the highway patrol officers arrive just in time and arrest him. She goes to Sam, crying and calling his name, while she hugs his lifeless body.
Starring Roy Thinnes as Architect David Vincent