This description by Helga Quadflieg

Returning from a her shopping in Foochow, Anne finds James and Baines arguing about the amount and quality of the provisions which Baines as Master of the Osiris wants to take for the voyage back. James, of course, wants to make as fast a voyage as possible and to spend as little money as possible. In contrast to his behaviour in the second episode, however, he refrains from commenting on Anne’s purchases and throughout  the voyage James and Anne present an image of  sheer marital bliss.

This contrasts  sharply with the state of Elizabeth’s marriage: Fogarty discovers Albert in the company of the music hall singer Carrie Harries. Later, in a chance meeting with Elizabeth he lets slip part of this information.. When confronted with this by Elizabeth, Albert is far from showing signs of guilt, but in return accuses Elizabeth of coldness towards him.

Meanwhile on the Osiris, Anne and James are  nursing John Hennessy, a sailor who had been found floating (next to a second  - dead - man) in a lifeboat.

By and by they  learn that Hennessy is the sole survivor of four men who had escaped in the lifeboat when their ship had sunk while taking the inshore passage round the Cape of Good Hope. The superstitious crew is highly suspicious of Hennessy: He quotes passages from Revelations about men being drowned by an angry sea; he doesn’t eat meat; his last two voyages ended in disaster and shortly after picking him up, the Osiris [nomen est omen!] is thrown off course in a terrible storm in which one man loses his life. At least for two of the crew members these are indications enough that Hennessy is a “Jonah” who brings bad luck. After the two trouble makers tried to kill Hennessy, Baines wants to leave the man in Durban, but James objects because this would mean losing too much time. Baines reluctantly has to bow to the “owner’s order”, but is visibly offended by this infringement of his authority.

Hennessy recovers and later surprises the two troublemakers privately trying to kill the pigs which are being kept to provide meat for the crew. Hennessy is attacked and severely injured. Just before dying, he confesses that  he himself had killed the second man in the lifeboat in order to prevent the man to do the same to Hennessy what he had already done to the other two: kill them and drink their blood. Hennessy’s death coincides with the end of the lull which had kept the ship until then.

While Anne in the end succeeds in persuading James to restore Baines’ authority and self-respect by no longer interfering with his command, the estrangement between Albert and Elizabeth  is underlined when Fogarty pays her a visit during Albert’s absence and when he arrives Elizabeth is bathing William, Daniel Fogarty's son, she openly discusses openly discusses her frustration with her marriage. But says she made her choice.....