I thought this was going to be a gothic. It was published in 1963 by Fawcett and the cover shows a woman apparently running from a tall man and a dog, with a farmhouse behind them, a crooked black tree, and a full moon. That's gothic. But the book is--well, not exactly a thriller, and thrilless isn't a word. I guess I'll tag it suspense, although there wasn't much suspense either.
It's a peculiar book. There are a lot of mysteries hinted about in a few characters' pasts and I expected these to be tied into the main plot. I was wrong. The hints never materialized into revelations. There's nothing going on in the plot that we aren't shown or told, so there's nothing much to wonder about.
Pat O'Shea, a college math teacher, chases after a colleague who seems to have stolen an expensive item from the biology lab. He intends to force a confrontation, but the colleague is out of his mind, attacks Pat, and leaves him for dead at the end of a dead-end street. A crazy old woman finds him and thinks he's her long-lost son. She takes him home and keeps him a virtual prisoner with her ferocious dog, not to mention that Pat's been badly injured. The rest of the book is mostly everyone looking for Pat.
The plot is supplied by near misses. Pat's wife almost drives down the dead-end street when she's out looking for him, she almost speaks with the boy at the gas station who saw where he went, another character almost gives the police the right information. After the first few almosts, I wanted to throw the book across the room in frustration. The only reason I kept reading was to find out the big revelations at the end--and, as I've said, they never came.
The writing is pretty horrible. Armstrong tells-not-shows constantly, with lines like "The girl's voice was low and it evaded. She was nervous. She was pitiable." That's not writing, it's outlining.