Sister Pereria (from series 2) returns bringing in her son for treatment. DeVries finds out about the blood group and that the boy is his son. Dr. Mortimer tries to teach Mr. Docherty how to dance! A Wharfarin overdose patient initially refuses treatment with a blood transfusion because he is a Jehovah's Witness. When the patient suffers a stroke, he appears to change his mind, however in a seemingly uncharacteristic act of Dr. Collin, he suddenly tries to persuade the patient to continue to refuse treatment with the blood because of religious beliefs. Liz starts to crack under the pressure.