David is rushed into hospital, and immediately lost in the system by the young houseman Phil Brooke (later to reappear in Health & Efficiency) While Bill, Ben and Jenny wait for news concerning the tetanus he has developed, and where he is, Rona gets a bus to church. On the bus she meets a strange lady who reminisces about an old song called ""The Girlfriend of the Whirling Dervish"" concerning a promiscuous woman who cheated on her faithful boyfriend. At the church, the ceremony is transformed, in Rona's eyes, to a mass rendition of the number, signifying her inner feeling of unsuitability for this marriage. She bolts a second time. At the hospital, with David near to death, the biker appears to him, on his final mission. He persuades David to return to his parents, who clearly love him dearly. Rona feels sad but relieved, and they all go out in a monster truck on David's release from hospital. (thetvdb.com)