The Emperor Hadrian, approaching the end of his days, writes a valedictory letter to his eventual successor, Marcus Aurelius. He reflects on his life from his childhood in Spain, through his career as a young military officer, his political machinations in Rome, his eventual accession as Emperor following a death-bed adoption (possibly contrived fraudulently) by his predecessor, Trajan. He explains his policy of stabilising, rather than expanding, the empire, of preferring trade to conquest. He tells of his extensive travels to the furthest limits of the Empire, and recounts the story of a homosexual love affair that ended in tragedy on the Nile. He reflects, also, on death, on culture, on the nature of love and of the human condition; and he provides advice to the younger man, advice which he knows may not be wanted, but which he feels it his duty nonetheless to give.