The quest for the Holy Grail is part of a long literary tradition, and Sutcliff depends heavily on her sources for themes and for characterization. Following Malory's lead, she focuses on the moral dimension of the tale. Sir Lancelot, Sir Galahad, Sir Percival, and Sir Bors—each searches for the Grail for his own reasons, and each comes to know something about himself through the quest.

For a knight to achieve the object of his quest, he must put aside all temptations and pleasures of the flesh and commit himself wholly to spiritual perfection. In The Light Beyond the Forest, Sutcliff shows how the path toward perfection is strewn with temptations in many guises. Many try to find the Grail, but only the most perfect knight will succeed.

Sutcliff depicts the dangers that lurk in wait for the questing knights. Even these four...