Helliconia is a planet that due to the massively eccentric orbit of its own sun around another star experiences seasons that lasts eons. Whole civilisations grow in the Spring flourish in the Summer & then die in the brutal winters. The human-like inhabitants have been profoundly changed by their experience of this harsh cycle. In orbit above the planet a terran mission struggles to observe & understand the effects on society of such a massive climatic impact. Massive thoroughly researched minutely organised full of action pulp references & deep drama this is a classic trilogy.