In this tale, the unlikable leper, Thomas Covenant, is pulled back to the Land by the summons of Elena, high lord of Revelstone. But a few weeks have passed for Covenant since his first adventure, but a full forty years have passed in the Land. The time of Lord Foul's victory draws near as Lord Foul's minions mass for imminent war. They hope that the power of white gold can save them.
On this visit, Covenant finds that he's not the only real-world person drawn into the land. Another person, Hile Troy, had been summoned years before and has risen to the position of General. He's not counting on magic to win, but his use of strategy and tactics. He'll have his work cut out for him, because Lord Foul has a fantasy army of unstoppable proportions.
The work itself contains a split narrative. Midway through the book, Hile Troy becomes the main character as we follow the desperate Illearth War. Meanwhile, the final third follows the quest of Covenant and High Lord Elana.
If you expect a happy ending, you've got another thing coming. This is a Thomas Covenant book. Not having every burn in Hell counts as victory (but some people are going to burn).
The fantasy war itself remains Tolkienesque. While the human army tires, needs to eat and drink, and suffers from mortality, Foul's army mysteriously never tires, nor hungers, nor anything. He's got a perpetual war machine going. This is pretty normal for "overwhelming invasion" fantasy stories.
Covenant himself gets more bearable if you just skip most of the text. This is an easy book to skim. Most of the description doesn't add to the story. Skimming also helps you to skip over all the self-loathing and angst, which helps immensely.
I first ready this book back in 1979, and it was massive and huge and all sorts of awesome. How well has it stood the test of time? Like platform shoes and heavy sideburns, the book shows itself a relic of its time. Take away the angst, and the story itself becomes astonishingly simple, with very little for Covenant to do. He influences events, but almost never by his own choosing. For most of the work, we can substitute him with a recording that says, "Don't touch me," and "Hellfire," and never notice that he's not a real person at all. The only major woman in the story requires trigger alerts. [Warning: Icky ahead. Really.] Yet, the story also shows itself more progressive than would be expected. Both man and women are in the armies, earning rank equally. Even this mere attempt at inclusiveness puts this work far ahead of many SFF works of the day.
The book still deserves its place in the 70's as one of the best fantasies out there, but in the larger SFF literary context that's emerged since that decade, the reader has many more engaging options.