You heard the beginning of this story often enough: a wealthy plain looking woman married a handsome younger guy (would "bought him" be a better term?) The only two things the latter has are exactly the ones I already mentioned: youth and good looks; the money comes from his wife. At one point he increased his demands for money; the wife refused him and - to her complete surprise - he continued his lavish lifestyle without visible means of supporting it.
Nero Wolfe avoids divorce cases like a plague, but this time it was only figuring out the source of the guy's income, so the detective decided to take a case; his bank account (poor state of it that is) helped with the decision. The problem comes when it turned out his investigation would make a very powerful person slightly inconvenienced. Such people think nothing about killing anything that stands in their way, like Nero Wolfe and Archie Goodwin in this case.
This is a very unusual Nero Wolfe novel as the latter has to break his routine of the previous sixteen books completely. I really cannot say anything at all to avoid spoilers, but the first time I read it I was in for a big surprise. My standard disclaimer applies here as well: do not read the book's blurb as it will spoil quite a lot. Let me just say Archie Goodwin has to work on his own here and he shows himself a very competent detective, even if not quite on the level of Nero Wolfe's genius.
5 stars for highly entertaining value is the final rating.
This review is a copy/paste of my LeafMarks one: https://www.leafmarks.com/lm/#/books/144974