Widow's Wake is the last of three in The Sisters' Saga, which tells of three sisters and the compromises they must make to reconcile love's delusions with the demands of reality. Recently widowed for the second time, Lady Henrietta Wood's funds fall well short of her preferred lifestyle. In 1847, she sets sail from Sydney to London, intent on wresting a higher pension from the Colonial Office. Her leverage is a set of secret documents of great importance to the British Government's relationship with France. Her brother gives her the first of two packets, with the other yet to come.

Her fellow passengers include Mr Morgan Mayhew, who is returning to marry his childhood sweetheart, and war-hardened Lieutenant Gordon, whom her brother warns her against. Henrietta paints herself as the heroine of the colourful tales she tells young Mr Morgan Mayhew of her many adventures. As their journey progresses, Henrietta must find an ally if she is to complete the mission. But is young Mr Mayhew man enough for the task?

Over the course of this eventful voyage, Henrietta must reconcile the regrets of her past in order to truly cast aside her widow's weeds and embrace the adventures ahead.