The plot is pretty simple: an ill man visiting Brighton to restore his health witnesses a crime; years later, his best friend marries, and he discovers that the wife is the woman he saw that fateful night in Brighton. She seems nice, so moral dilemmas ensue. It ends in a convenient but unsatisfying way.
The thing that I found rather unusual here was the book's portrayal of the protagonist's relationship with his friend. One passage to give the flavor:
"You can imagine how I loved Lance Fleming; the love that other men give to wives, children, parents and relatives I lavished on him. I loved his fair, handsome face, his laughing blue eyes, his sunny smile, his cheery voice; I loved his warm-hearted, genial manner. In fact, I loved the whole man, just as he was, with a love passing that of women—loved him as I shall love no other."
That's not the only such sentiment expressed in the story. Presumably the author did not intend to raise any eyebrows by this -- but it is nonetheless interesting. It gets even more interesting and complicated when you consider that this is a book written by an unknown author (quite possibly, though not necessarily, a man) writing under a female name, writing a first-person male narrative. I'm sure somebody in gender studies could get a paper out of it somehow.
In any case, my quest continues -- next time, My Mother's Rival.