Splintered Light was her first book, establishing a reputation that increased with her later monographs Interrupted Music and A Question of Time, and two edited collections of essays.

It then compares and contrasts two of Tolkien's best-known essays, "Beowulf: The Monsters and the Critics" and "On Fairy Stories", the one essentially dark and fateful, the other bright, embracing the possibility of good fortune.

The story of The Lord of the Rings is covered in "One Fragment", in which, after the many disasters of The Silmarillion, the small remnant of the light survives to combat the remaining darkness.

[1] In the Rocky Mountain Review, the scholar and fantasy author Brian Attebery notes that Flieger shows how Tolkien followed Owen Barfield's views on myth-making, including the idea of a gradual fall from grace over the course of history.

In Attebery's view, Flieger successfully links Tolkien's Middle-earth writings to his scholarship, with a "well researched and sympathetic reading of The Silmarillion, a work whose importance she goes far towards demonstrating",[8] showing that even though it contains numerous short tales written decades apart, it is "a unified whole with a deeply felt meaning".

"[9] However, the core of the book for Neuleib is in the 3 chapters on The Silmarillion itself, in which Flieger traces the progressive splintering of the light created by Eru Iluvatar through the music of the Valar and on down to the Elves, Men, and Hobbits who people Middle-earth.

[9] The scholar of theology and literature Ralph C. Wood, reviewing another of Flieger's books for VII, writes that Splintered Light is "an indispensable work for any serious study of the great fantasist, especially of The Silmarillion".