HBO's Watchmen TV series follows on from the original 1980s comic, but fundamentally changes how its ending works. The finale of Alan Moore's Watchmen story sees Ozymandias succeed in unleashing a genetically engineered monster in New York City, staging an attack on humanity that he believes will ultimately lead to peace on Earth. Nite Owl and Silk Spectre fail to prevent the incident and admit defeat in each other's arms, Dr. Manhattan abandons mankind all together and departs for another galaxy, while Rorschach refuses to accept the situation and is killed for his moral absolutism, but not before sending a journal detailing the entire conspiracy to the press.
Damon Lindelof has described his Watchmen series as neither a remake nor a sequel, instead referring to it as a remix of the source material. Despite this, the HBO series does continue the story of the graphic novel, and is set in an alternate 2019 several decades after Ozymandias staged the attack from another dimension. A number of characters and stories are carried over from comic to TV including Laurie's return, the presence of squids and the position of masked vigilantes in society.
Somewhat unexpectedly, the Watchmen series carries on from the end of the comics, but deliberately goes against the grain of what the source material suggested. The most significant example of this is Rorschach's journal. At the end of the original story, a reporter picks the journal from a pile of random items sent to a newspaper, heavily implying that the truth will finally be revealed to the world. On TV, however, the world of Watchmen largely considers Rorschach's claims to be little more than another crank conspiracy theory - not the groundbreaking reveal suggested by the final panels of the comic.
Rorschach isn't the only character whose arc is turned on its head by the new Watchmen series. If Ozymandias' plan was to unite mankind behind a common enemy, then the villain has mostly failed. Adrian Veidt's squid hoax might've prevented a nuclear war between the world's superpowers, but it clearly wasn't the start of a brand new dawn for peace on Earth, as Watchmen's 2019 is even more violent and turbulent than the 2019 of the real world. Similarly, Dr. Manhattan's ending saw him depart the galaxy for a new one, but the shining blue nudist can be seen in TV footage during the Watchmen series premiere, proving that the God-like being is now working his way back home.
In an otherwise bleak ending, the romance between Nite Owl and Silk Spectre was a rare bright spot in the traditional Watchmen conclusion, yet even that seems to have been undone in HBO's continuation. While Jean Smart stars as FBI Agent Laurie (Silk Spectre), Dan Dreiberg is nowhere to be seen, debunking the implied ending that the couple would continue to fight crime on a less apocalyptic level after the Ozymandias incident. Furthermore, Laurie makes some pointed remarks about people who wear masks in the Watchmen trailer (Spectre never wore one herself) that sound like the remnant emotions of particularly messy break up. There's also a popular theory doing the rounds after Watchmen's premiere suggesting that Judd is actually Dreiberg - with the owl mug, the photo and Archie all pointing to this conclusion. If true, Dan and Laurie's relationship certainly didn't happily, since he ended up with another woman in Tulsa.
It's difficult to deny that the HBO Watchmen series fails to honor the ending of the comic books. In its own grim way, Watchmen gave its main heroes closure on their respective arcs, but now virtually every main character's ending has been untied in order for it to continue in 2019. Perhaps this is partly why Alan Moore has spoken out negatively against the new HBO series. But just because Damon Lindelof has altered the perception of Watchmen's ending, he certainly hasn't detracted from it. The darker continuation of the story, where no character really got what they wanted, is in keeping with the original in spirit, if not in a literal sense. Moreover, this was arguably the only way a sequel to Watchmen could work in the modern era - with neither the good guys nor the bad guys getting what they wanted. In the immortal words of the equally immortal Dr. Manhattan, nothing ever ends.
Watchmen continues with "Martial Feats Of Comanche Horsemanship" on HBO.