The Fixed Period is narrated in the first person by John Neverbend, and purports to be the memoirs of his time as the first President of Britannula, a fictional island near New Zealand. The story is set in the future, in 1980.

A group of elite New Zealanders have set up a colony on the island and have freed themselves from British sovereignty, determined to set up a fair and practical government. One of the major principles advocated and enacted by Neverbend is that of forced euthanasia within the state. The Fixed Period for life is sixty-seven years. During their sixty-seventh year all the citizens must go to a special college where they will be well looked after whilst they prepare for death, which must occur within the year.

President Neverbend selects Gabriel Crasweller, a close friend, as the first citizen of the colony to fulfil the demands of the Fixed Period Law; as Trollope points out the irony is that he is in excellent health. As the narrative progresses, Crasweller becomes less and less certain about the principles of the Fixed Period, but cannot back out due to his friendship with the President. Ranged against the fanatical Neverbend are his son Jack, who is set against the Fixed Period mainly because of his love for Eva Crasweller, Gabriel’s daughter; and Neverbend’s wife Sarah, implacably hostile to the whole principle of euthanasia.

Just as Gabriel Crasweller reluctantly agrees to go to the special college prior to his enforced death and is being driven there, a mob of Britannulans surround the carriage and inform the President that a British warship has docked in the port, its powerful guns aimed at the capital, Gladstonopolis. Already unhappy with the Fixed Period law, the citizens happily accede to the wishes of the British, and welcome their new Governor; the Fixed Period law is abolished, whilst Neverbend is taken to England from where he is free to write these, his memoirs.

The Fixed Period is one of the curiosities of Trollope’s oeuvre. It is his only futuristic novel; it is the only one to be written in the first person; it is also his most obviously satirical work, from the same sly mould which produced Swift’s A Modest Proposal. Legend has it that Trollope claimed that what was in the book was ‘all true’, but in reality what was preoccupying him at the time was his advancing old age. He had just moved house again, to Harting in Petersfield, the book had been written during the bleak winter months, and the slyest joke of all in the text was that Trollope himself was in his sixty-seventh year. The author’s thoughts had turned to death and dying, a theme that was reflected again in the central character of his next novel, Mr Scarborough’s Family.