3.5 stars, rounded up to 4 as per 5th grade math class.
Spoilers ahead: I'm on the fence about this series. I really liked the first book and gave it 5 stars but I didn't like the 2nd because it had a boring setting. The 3rd book was ok. Primarily I don't like this series because it has a long time antagonist or arch enemy. I don't like that because it limits the plot. It always has to do with the "bad man" who has to get away at the last moment in order to appear again.
In this case, Drinkwater's (ND) arch enemy is Santhonax, a French low level mover and shaker who is at the Red Sea to figure out a road for the French to descend down towards India. I mean, if this guy is so smart and so talented why does he antagonize the locals so much that they hate him and want to kill the French.
And what's worse is there is another "arch enemy", the midshipmen and now Lt. Morris who has seniority over him. The only reason to have these antagonists is for the protagonist to have some obstacle to overcome, a very cliched, overused and old fashioned plot device.
Summary: ND's commander Griffiths has now been promoted into a brig-sloop (Hellebore) and ordered to the Red Sea to put a spoke in Santhonax's wheel and find out what's going on. After half the book is over, the Hellebore is destroyed when 2nd Lt. Rogers runs it into a shoal in milky seas, then they find Santhonax careening his ship. Since their ship is gone, they get help from their Arab allies. They simultaneously attack the French on land and the ship and manage to capture it and sail it away.
They get back to base where the frigate is to sail home. Griffiths died in the attack and ND is promoted into commander of it but somehow Morris gets the command because the admiral wants to get rid of him. Morris proves to be a sadistic commander and everyone hates him.
They meet a French frigate on the way back and is only saved by Capt. White (who ND saved from Morris as a midshipman) appearing on the scene with his frigate. They finally reach the Cape of Good Hope. Morris sends a damning report to the commodore commanding but is countered by Capt. White and ND's own report. Morris has to go ashore because he's a sick man and ND is given command of the frigate to sail home.
But apart from the main story, there are a lot to like. I like the small subplots of which there are many, all character based. There is the story of Catherine Best, a prostitute convict being transported to Australia. Their ship was sunk by a storm and the Hellebore rescues the survivors. While on the ship she sleeps with a lot of the men to gain favors but ND finds out and stops her. He makes her the surgeon's assistant where she turns over a new leaf but then develops a serious relationship with the surgeon. At the end, Morris turns her in and she is forced to go to Australia but Appleby the surgeon decides to go with her.
Next is the redemption of 2nd Lt. Rogers who started out as an enemy of ND but due to the shared hardship and experiences ends as a friend and ally. After that is the midshipman Mr. Q, who is unfailingly helpful eager to learn. He loses his hand in a battle but I'm sure will turn up as part of ND's crew in the next book. Lastly is the colorful character Wrinch, who is the British representative in that area. He is also unfailingly cheerful, knowledgeable and helpful. Like Morris he is also a pederast but is given a pass in the book because he is ND's ally.
I think these character subplots are what distinguishes the ND books from the other ones like Ramage, Stockwin or Lambdin. In fact, this is what makes the Hornblower books great.
Overall, the writing is ok, the action is good and I like the character driven stories. I just hate to see the old arch enemies being recycled over and over again. I will try the 4th book and see if I want to continue.