This is the first book I've reread this year. I own all of Philip K. Dick's novels, but it's been decades since I read one, so I picked one I couldn't remember at all.
It's even better than I thought. When I first read all his books, in my teens and 20s, I was absorbed exclusively by the reality-bending stuff, and hadn't lived enough to appreciate the psychological insights. Compared to most science fiction, his characters have much more realistic concerns, even as they think they're going crazy because reality is flaking off like a bad paint job. The protagonists in this one work in a grocery store, raise kids in the suburbs, petition the city to clear old lots, and belong to the book of the month club. There's a female character of substance and intelligence who is not a romantic interest. (There's a romantic subplot that's a bit male fantasy, and a bit squirmy if you've read about PKD's personal life, but even that reeks of anxiety and plays out into a mess.)
The main guy sits around his sister's living room, drinking warm beer and solving a puzzle in the newspaper called Where's the Little Green Man? He's the national champion. It's stressful; he's terrified of making a mistake and getting booted out of the contest and then what would he be? Some schmuck without a job, mooching off his sister.
Except strange little things keep happening to him, his sister, and her husband, like habitually reaching for something that isn't there, and finding an old phone book full of numbers that don't exist, and a magazine that talks about some famous movie star that none of them have ever heard of. 90% of the book is them trying to understand these weird anomalies, which slowly eclipse their ordinary concerns.
Ragle Gumm, newspaper puzzle solver, slowly pieces it together and towards the end, we get into dystopian science fiction country. But what I get now that I didn't get as much when I was younger, is the psychic import of the journey. He has to go through this terrible land of not-knowing & wrongness in order to reclaim himself and ultimately connect with other people. It's primal, mythic, but it's also solidly anchored in a specific setting. Like searching for a gas station late at night on the edge of town = searching for the boatman to cross the Styx. There are echoes, even in this early work, of the religious preoccupations that would flower so beautifully in his final few novels.
So yeah, Philip K. Dick. If you've never read him, you've probably seen movies based on his work: Blade Runner, Minority Report, Total Recall, A Scanner Darkly, and many more. Trust me, the books are much better. There is no greater science fiction writer.