Duncan is sick of the purser offering medical advice and the purser is anxious to rat on Duncan to the captain for taking bribes from the kitchen. After the couple have publicly come to blows, the purser disappears and Duncan is suspected of killing him. The purser reappears, having got locked in a store room and escaped through the ventilation shaft, and the feud continues.

The Begonia comes home after the cruise and Duncan, having fallen out with Dick, decides he has had enough of being a ship's doctor and returns to St. Swithins. Things have changed but Sir Geoffrey will have him back - and Dick too. Should they accept? Or should they return to the Begonia?