On the first page, we have a character's anxiety laid bare in a sentence: "He did not belong here, among these sailing folk with their lazy expertise; he knew it, and they knew it, too, which meant they had to behave twice as heartily towards him, though he could see that look in their eyes, that gleam of merry contempt."
Black -- is it conceit or challenge -- neglects to straight-out state when his book takes place. If this is the first of his books you are reading, you must follow the subtle clues that set the stage in the 1950s.
Although the book begins with a suicide, it's less about what drove Victor Delahaye to this desperate action than what drives his little circle of family and business associates. He had a trophy wife, malcontented twin sons, invalid father, repressed sister, and a business partner who despised him. Victor, his family, his partner, and his partner's family were all on their annual self-flagellating vacation in an Irish village by the sea when Victor bid adieu.
Enter Dr. Quirk, a Dublin pathologist, on the heels of his more-than-acquaintance-less-than-friend, Inspector Hackett. He is drawn into the tableaus the two families create. Vengeance is a string of scenes suspended in amber, most having to do with the two families but some having to do with Quirk's personal life. The two begin to intertwine in a lazy way, pointing out, of course, Quirk's constricting flaws. They've already been explicated in Christine Falls, The Silver Swan, Elegy for April, and A Death in Summer.
Victor Delahaye shot himself in a boat. With him was the shocked 20-something son of his business partner, who throws the offending pistol overboard in a state of panic. Will he be accused of the crime? Is this the book's story? No, the son's tale is believed, and he is not held to account. Well, what then? Among Victor's last words are: "[Y]ou must know about loyalty--eh? Or the lack of it, at least." And that is the slim trail the reader must follow to find out what the real crime is. A bona fide murder eventually follows, but it is simply a piece of the unraveling of the two families.
I delight in Black's language. Hackett, asea in a soup of his betters, "felt like a monkey with a coconut and no stone to crack it on." An aged relation and progenitor of one of the current partners is described:
As a young man Philip Clancy had been tall and thin and now he was stooped and gaunt. He had a small head with a domed forehead and a curiously pitted skull on which a few last stray hairs sprouted like strands of cobweb. His nose was huge and hooked, a primitive axe head, and his mouth, since he had given up wearing his dentures, was thin-lipped and sunken.
It is not until page 213, that we get a concise and vivid round-up of all the characters. From this point until the end, there's a bit more mystery-solving and tidying up. You might be able to skip to this point and just read the last 100 pages. However, you'd miss a master at his craft.