Complete Monster: Blofeld, having plastic surgery again, has multiple diamonds stolen to power a satellite with an orbital laser. Blofeld calls an auction between the Soviets, Chinese and Americans: the winner will possess nuclear supremacy in the world, while the losers will have their countries wiped out by the satellite.
Ensemble Darkhorse: Mr. Wint and Mr. Kidd. Various shows have parodied the characters and there's even a jewelry store in London named after them.
It was good that Lana Wood (Plenty) and Jill St John (Tiffany) barely had screentime together, given that both women and Robert Wagner allegedly had a falling out over Lana going to the media with her version of the events that led to the drowning death of Natalie Wood.
Genius Bonus: Bond's line, "Alimentary, my dear Leiter" almost didn't make it into the film. The line refers to the Alimentary Canal, another name for the Gastrointestinal Tract, which terminates in...well, you know what. Apparently, Albert R. Broccoli demanded that screenwriter Tom Mankiewicz remove the line for fear that nobody would get the joke.
Harsher in Hindsight: On a related note, the one scene that Jill St.John and Lana Wood appeared together in had Tiffany Case go into her house, finding Bond standing by the swimming pool and Plenty drowned in the middle of the pool.
Lana Wood would later play the lover of an evil demon played by Kabir Bedi, who plays the evil henchman Gobinda in the 1983 Bond film Octopussy. The film being Satan's Mistress (also known as Demon Rage).
Magnificent Bastard: Blofeld made good use of decoys this time around. He used not only one, but multiple decoys of himself and when Bond meets him and a decoy later in the film, not knowing which is which, he scares the cat and kills the one it runs into, but it turns out the cat was a decoy too. The real cat wore a diamond collar, as seen in the intro. Well played, Blofeld.
The cremation scene. Getting cremated alive has got to be the most horrific way to die imaginable. The music playing during that scene hardly makes it better.
The poor PLA soldier's death by Kill Sat above. He gets set on fire and dies being burned alive.
Plenty being caught almost completely naked... and then drowned, with the camera helpfully panning down her body towards the large weight she was tied to as slowly as possible.
Older Than They Think: Many fans complained that Blofeld had a full head of hair in this movie instead of his iconic bald appearance of the previous two films. In fact, Blofeld did have hair during his appearances in From Russia with Love and Thunderball, though it's difficult to see due to his face being obscured in those films. On top of that, the literary version was also described with an appearance close to that of Charles Gray in this film; in fact, the only reason why the screen Blofeld was ever bald was that Donald Pleasence happened to be bald himself.
One-Scene Wonder: Plenty O'Toole. Even more so after she decides to let Bond deprive her of her clothes.
Charles Gray's interpretation of Blofeld is arguably the least popular incarnation of the character to date, being much less menacing than his predecessors.
Tiffany Case, who very quickly becomes a Damsel Scrappy as she comes to rely on Bond to save her hide on one too many occasions.
Norman Burton as Felix Leiter, who comes across as being far more bad-tempered and useless than his previous appearances. It doesn't help that this comes right before David Hedison's version in the next movie, which (at least until Jeffrey Wright came along in the Daniel Craig films) was widely considered the most popular incarnation of Leiter.
Sequelitis: It's widely considered Connery's weakest and among the low points of the series for its campy tone and delirious plot.
Special Effect Failure: Connery's increased salary for the movie meant that a cheaper effects company had to be used to cut costs.
During the chase scene with the moon rover, you can see a wheel rolling on screen just after the rover goes off camera. This is because they crashed the rover.
During the chase through the Las Vegas Strip, Bond drives his Mustang through a narrow ally on the two wheels of his right side, only to exit the alley on the wheels of his left side. Chalk this one up to bad editing, one which the filmmakers attempted to rectify by simply flipping the shot of Bond and Tiffany inside the car.
The Kill Sat itself, which somehow manages to look worse and worse in each shot. In the shots of the rocket launching and separating it actually looks decent, at about the standards of the similar sequences from You Only Live Twice. When the satellite sheds its outer casing and fully deploys, it looks like something you'd see in a cheaper episode of Thunderbirds. By the time it takes out a Chinese military base, the effects standard has dropped to being barely above a contemporary episode of Doctor Who.
As terrifying as the scene of Mr. Kidd burning alive is, one can clearly make out Putter Smith's heavy fire retardant gloves as he is set alight. Moments later, when Mr. Wint is blown up by his own bomb, none of his remains can be seen falling into the water.
Willard Whyte has installations all over the place; Alaska, Florida, Maine, Oregon, Texas, Baja — wait, he doesn't have anything in Baja? The villains could've set up anywhere along any coastline, and they choose the one place Whyte knows he doesn't have any property? And then they mark their secret base on Whyte's map?
The biggest problem seems to be not that they used Whyte's name to buy it, but that they built a model oil rig and put it on his giant floor map of property. Nobody exactly comes up to see Whyte, and those who have access to the room and know about the purchase likely wouldn't question the lack of a marker simply because it's not a big deal (and those who have access are probably in on the plot to hold Whyte hostage anyway). Literally the only person who would actually notice them marking their secret base is the person who could blow the lid on the whole operation. Had they not bothered marking the purchase, they'd have had to search every location on the map and give Blofeld all the time in the world to laser cities.
How Plenty O'Toole got herself into her chilling fate, which has been a mystery to fans and viewers for years. Plenty's unfortunate send off was the result of a deleted scene where after getting thrown out of the hotel room and into the pool a soaking wet Plenty, wearing nothing but a white Modesty Towel and carrying her purple high heels (it is not addressed whether or not she still has her iconic transparent pink panties) returns to Bond's hotel room in the hopes of retrieving her clothes and seeing what's happened to him - and is positively outraged to find Bond having sex with Tiffany Case. Before leaving in a huff Plenty rummages through Tiffany's purse and finds her address, so she later went to Tiffany's to get even. It didn't go well for her... A bit of unintentional yet amusing Fridge Horror here is that without this deleted scene one is left with the idea that Plenty possibly had to return to her home WITHOUT her proper clothes.
Nausea Fuel: Fleming lovingly draws out every single detail of how disgusting the mud baths at Saratoga (not to mention its customers) are. It's topped off with one of the most disturbing torture scenes in the book, if not the whole series.
The Scrappy: Jack and Seraffimo are easily the least liked of Fleming's main villains, being completely mundane gangsters with completely mundane motives. It's probably telling that they're the only Fleming Big Bads never to have been adapted to film.