I first read this trilogy as the books were being published in the early 1980s. Recently, I re-read them. Chronners may know that I think of this work at the top of the SF tree, though it's not perfect. Yet for vision, grandeur, inventiveness and audacity there's nothing really to match it, except The Book Of The New Sun and Dune.
The set up is this. An ageing G4 star with planets, one of which sustains life, is captured by an 11-million-year-old white supergiant, so that the former starts orbiting the latter. This entirely changes the course of evolution on the life-bearing planet. Aldiss' trilogy takes three points on the 1825-year Great Year, when winter's ice starts melting, the burning chaos of summer, and the powerfully gloomy descent into another great winter, and within them tells three tales.
Helliconia Spring relates the story of the impoverished residents of Oldorando at the equator, where centuries of ice and snow begin melting. Though the vast scale of the planet and its myriad of life forms dominates, the scale of the human-like (identical, basically) characters, with their petty jealously, anger, lust and desire for power, makes an awesome contrast. These are tiny people living in a huge environment.
The humans aren't the only characters, however. Before the stellar capture, an alien race, the phagors, ruled the planet. Amongst SF's best aliens, the phagors' eotemporal minds, recalling the catastrophe of the stellar capture, all hate the "recently arrived" humans, who in former times were their hominid-like pets. The interplay between humans and phagors is one of the forces of enantiodroma, things turning into their opposites, which drives the complex and engaging plot.
Now it is summer, when the planet is closest to the white supergiant. The ice-loving, antifreeze-blooded phagors are in retreat, confined to their stratosphere-grazing High Nyktryk mountains. Human beings are free to fight wars, have affairs, hate their fathers, miss their sons, and in general do all the petty, irrational things human beings are so good at. But all this is being watched by the Earth humans of an interstellar expansion from thousands of years ago, including Billy Xiao Pin, who's won the Helliconia Lottery, allowing him to go down to the planet’s surface. Because of the hellico virus, however, which physically transforms Helliconia's humans in preparation for warmth and for cold (bone fever & the fat death) his win is a death sentence.
Meanwhile, the King of Borlien is about to divorce his wife in order to marry a young nearly-human girl, a dynastic marriage that he believes will save his country. Chaos ensues...
The great planet is descending into a centuries-long winter. In northerly Sibornal, the autocratic Oligarch is making increasingly more drastic laws to "protect" his people from the plague - the fat death, as it's called at this time of the Great Year. In Kharnabhar, high in the mountains, we meet our hero, son of the Keeper Of The Wheel, an immense subterranean religious machine of stone and metal chains. Yet the Keeper's son is caught up in these draconian measures, and tries to sidestep the laws and outwit his father. In doing so, he reveals the horror of his own family, and the lengths some people believe they must go to in order to survive at a latitude where, for three and a half centuries, the white sun will never rise above the horizon.
It's impossible to convey the majesty of these books in a few sentences. In a sense, there are two stories to the trilogy, one of the humans and their lives, interacting with one another and with the phagors, the other of the planet itself. Aldiss, inspired by the then recent and paradigm-busting Gaia Hypothesis of James Lovelock, invented a Helliconian equivalent, which the inhabitants know of via their religious lives. Lovelock would have been annoyed by the association, but there's no doubting it's power and efficacy when it comes to this exceptional work of fiction.
The trilogy isn't perfect. Some of the prose is a tad clumsy, there's head-hopping and other flaws, but as a whole the work is stunning, highly readable, complex, fascinating and marvellous. Its sheer joi de vivre carries it along: the fruitful multiplicity of life as it evolves, the interaction between climate and life, and between geology and life. All this is witnessed by tiny human characters as they live out their tiny lives, dwarfed by the grandeur of the planet which brought them into being.
