It tells the story of the life of Arthurian legend character Morgan le Fay, presented through an oral history narrative from her early childhood to her disappearance.

An ebook version of Morgan le Fay was also released by Wildside Press, through the Google Play service.

[2] As described by the author, "Four people tell Morgan's story: two women, two men, two pagan, two Christian, two sympathetic, two hostile.

Arthur is the result of Uther Pendragon's deception of her mother Ygerne and his killing of Morgan's adored father.

Uther fell in love with Ygerne when Gorlois brought her to court and pursued her to their fortress in Bossiney.

When Gorlois goes out to fight Uther, Ygerne and her three daughters retreat to the nunnery on the headland of Tintagel, protected by the formidable abbess Bryvyth.

After two years she is promoted to help in the library, when she witnesses the dramatic expulsion of Ygerne after Uther tricks his way into Tintagel.

Morgan joins with other nuns who secretly follow the old religion, meets with her old nurse Gwennol on the beach below Tintagel, and is taught the magic craft.

Morgan remembers how Uther Pendragon killed her father and came to Tintagel disguised by Merlyn to conceive Arthur on Ygerne.

Merlyn wants Arthur to marry Gwenhyvar for her royal blood; on their wedding night, a heartbroken Morgan beds with Accolon.

She moves from Geoffrey of Monmouth's wise ruler of Avalon, through a fairy healer and giver of magical gifts, to an evil witch and lascivious seductress in the version by Thomas Malory.

She becomes Arthur's sister, and the enemy of lovers; she is the ambiguous Loathly Lady and the ominous Washer at Ford.

Morgan reviews the progress of her legend through the ages, down to revisionist modern writers and even the author of this very book.

"Just Cause", the tale of Morgan and Accolon as told from Uwain's point of view, is a related[4] short story that was published in the 1997 anthology The Chronicles of the Round Table.

Another short story, "Ravens' Meat", related to The Dream of Rhonabwy, was included in the 1998 anthology The Mammoth Book of Arthurian Legends.

The third of the short stories, "The Test", was published in the 2005 anthology Strange Pleasures 3, retelling the plot of Sir Gawain and the Green Knight from Morgan's perspective.

Some of the wildness and the evil that are conventionally attributed to Morgan reminded me of girls who might be into drugs or delinquency in some form, and it was that kind of "perverted" figure, I suppose, that I was thinking of at that time.

[2]Sampson began writing Dark Sister many years before the publication of the first volume in 1989, later expanding the scope first into two, then four, and finally five books.

[2] Sampson would read Marion Zimmer Bradley's 1983 Morgan le Fay novel The Mists of Avalon only while writing the very last part of Herself, as her editor had forbidden her from doing it earlier.

[2] According to Leila K. Norako, "the descriptions of the pagan ways are far less detailed and developed (and therefore less overtly neo-pagan) in Sampson's novels than they are in Bradley's.

"[7] As for her inspirations, Sampson said she tried to "preserve the element of healing," associated with Morgan's original named appearance in Geoffrey of Monmouth's Historia Regum Britanniae, and was least interested in the Holy Grail story in the later medieval evolution of the legend.

Developing the relationship between Morgan and her sisters Margawse and Elaine, Sampson was influenced by Robert Graves and the triple goddesses of the Celtic mythology.

She also credited Lucy Paton's Studies in the Fairy Mythology of Arthurian Romance as her most useful source for additional research.

[2] Sampson said she was not "interested in the kind of feminist writing that just reverses roles, seeing Morgan as good and Arthur as bad.

Magazine praised the first book, Wise Woman’s Telling, for "inject[ing] new life" into the Arthurian legend, adding that "the undercurrent of paganism has a grim and messy conviction about it, and likewise the Dark Age brutality;"[8] by the time of the fourth book, Taliesin's Telling, G.M.

[10] According to the 1997 Encyclopedia of Fantasy by John Grant and John Clute, the series has been Fay Simpsons's most notable achievement in adult fiction by this point;[11] they also suggested Herself as "further reading" in the entry for Morgan Le Fay for its meta discussion of relevant literature and the transformation of the character.

[12] Grant, in his 2002 guest review in Interzone, described the series as "outstandingly different in both style and mood" than most other Arthurian stories, "well out on its own limb (and excitingly so).

"[13] According to Professor Raymond H. Thompson, what emerges from the books "is a complex personality [of Morgan], but one that continues to fascinate, as she has done down through the ages.

"[2] In 2015, Cindy Mediavilla in Arthuriana chose it as one of the few examples of literary depiction of Morgan le Fay where she "progressed from a one-dimensional evil-doer in early classic children's stories to a fully-realized heroine", alongside Bradley's The Mists of Avalon and Nancy Springer's I Am Morgan le Fay.

[14] Also writing in Arthuriana, Professor Jacqueline Jenkins included Fay Sampson among the "undeniably influential participants in the retellings of the Arthurian legends with broad audience appeal.