Central HQ has to be quarantined after a boy is brought in suffering from a mysterious disease. Two crazy criminals are bringing trouble, too. The other officers investigate the past of the boy and find a puzzle piece in his ""bomb"". We learn that Grossie is learning Russian.

Ponch and Jon become involved in the case of a young girl whose parents are nowhere to be found. Candi, a racing driver, takes her to the racetrack - with dramatic consequences.

Candi tries to help the young girl who is unhappy at her foster home. Ponch and Jon move in on the crooks that they have been watching.

Officer Bonnie Clark believes she was forced off the road by a truck after crashing on a dangerous mountain road.