I wish Amazon would incorporate 1/2 stars but I guess that would make things even more complicated. This is one of my favorite Hemingway books and one of the few published posthumously that lives up to his legacy.
The book, broken into three distinct sections, recounts chapters in the life of Thomas Hudson, a somewhat thinly veiled version of Hemingway. That's not to say that this is a story about Hemingway himself, but its pretty clear there is a lot of Hemingway in Hudson.
The first section, considered by many to be the best (and, as a I recall, the focus of the film made of the book), takes place in Bimini, where Hudson is leading a fairly idyllic life. The second is centered in Cuba but has an entirely different tone from that of the first. Whereas the "Bimini" section is almost light-hearted and somewhat breezy, the tone of the Cuba section has changed dramatically. Hudson is now a depressed individual having lost a son in an accident. He has a reunion with his first wife, but even though she is the love of his life, he knows it won't end happily. The third part, "At Sea," recounts Hudson's efforts as a Nazi sub hunter.
Hemingway is at his best throughout much of the book, his men are all striving to prove that they are, well, men, or at least the ideal of what a man should be in Hemingway's eyes. And naturally enough, no Hemingway man, in this case Hudson, would be complete without a little tragedy in his life. "At Sea," while powerfully told, seems somehow incomplete, which may well be the case since I do not think Hemingway completed the book before his death. In fact, the ending seemed extremely abrupt and left me wondering, did Hudson survive his wounds?
Still, this is some of Hemingway's best work. A must read. The only reason I did not give it five stars is because of the abrupt ending and a few other brief passages in the book that seem somehow incomplete and unfinished.