Kate Wilhelm has long been one of my favourite SF writers. I like her mysteries too, but it's her SF that I find really remarkable. It isn't hard SF. It isn't exactly soft SF. It's more like... psychological SF. I think it's a precursor of cyberpunk, if you can imagine cyberpunk without either the 'cyber' or the 'punk' aspects - and it has the flavour of some of the mindbending drug-related fiction that was popular in the 1970s and 1980s.
Today I read one of her earlier novels, Abyss, from 1971. It's actually two novellas packaged as one book - it would have been nice if the publishers had mentioned this on the cover. The first story is about a family in which the wife of the scientist is experiencing odd continuities and discontinuities in time and space, along with strange visions of a dark, square city. She often finds herself in two places at the same time. Her husband thinks it's a hoax; others are less sure. It's a lovely, moody story, in which developing relationships really have pride of place.
The other is about an alien stranded on earth, trying desperately to make friendly telepathic contact with certain Earthmen, and failing - largely because the humans instantly perceive him as terrifying and demonic, and his kindest thoughts come across as full of hatred and pain. An oddly disquieting story, with the mood of a ghost story.
Both stories were light on plot and heavy on atmosphere, both strangely compelling.