The draw of most action films are fast-paced fights and battles, but most still manage to end with the good guy standing and the bad guy dead. The alternative, though rare, shocking, and often depressing, can still be a ton of fun in the right context.
The most common downer ending for action cinema comes in one part of a larger story. The middle part of a trilogy often features an "all is lost" ending to set up for an even more satisfying victory in the end. Even so, the occasional opportunity to see the villain stand atop their kingdom, if only for a moment, is still interesting. Spoilers ahead for every film mentioned.
Avengers: Infinity War
Everyone knows how this goes. Infinity War is Thanos' movie, his chance to finally take the spotlight he's teased for the previous several years. He does so with great aplomb and people have been lining up to praise him as one of the best villains of cinematic history ever since. Yes, Thanos claims the Infinity Stones one by one. He defeats the army of heroes who rise up to take him on and undergoes every sacrifice and trial necessary to get his hands on his weapon. He succeeds thanks to overwhelming natural power, unstoppable ambition, and reckless willingness to do anything in pursuit of a terrible goal.
Unlike any other Marvel Cinematic Universe film, this one ends on an immediate and nightmarish moment of death. Thanos wins, half of all life is destroyed, and the audience gets to enjoy the spectacle of several of their favorite characters reduced to dust. The blow is softened by immediately watching Endgame, but people cried in the theater back in 2018.
Man of Tai Chi
Keanu Reeves' directorial debut is a fun martial arts romp that gets a bit muddled in the narrative details. The weirdest part of it is probably its final battle and resulting ending. Throughout much of the film, peaceful Tai Chi master Tiger (Tiger Chen) is egged on by his nemesis, enigmatic warrior Donaka (Keanu Reeves), to use his skills to kill. Donaka pits Tiger against one foe after another, philosophically convinced that the stronger foe will eventually kill the weaker. Tiger wins every battle and carries on his way, until the fight with Donaka himself. Donaka explains that his pupil is becoming more ruthless, more violent, slowly succumbing to his baser urges. Tiger challenges Donaka, wins despite a stab wound, and kills Donaka in combat. Tiger wins the fight, but, in doing so, becomes a murderer. The movie fails to give that moment the impact it deserves, but, Donaka dies victorious, even if the background music insists upon a happy ending.
Upgrade
Leigh Whannell's killer AI horror/action film is a bizarre mixture of offbeat comedy and grim cyberpunk dystopia. The film uses body horror as gross-out, punchline, and action setpiece. The main character Grey finds himself crippled, and his beloved girlfriend murdered after a chance encounter with a gang of violent thugs. A reclusive tech billionaire gives Grey a neural implant that gives him back the use of his limbs, along with much more. With his new physical capabilities, Grey begins the path of seeking vengeance for his circumstances.
Unfortunately, the villain isn't the people Grey hunts down, the billionaire who gave him the tools, or Grey himself. It's the neural implant itself, which has become self-aware and seeks an obliging body it can use to claim dominance over mankind. Through Grey, it finds that slave. Upgrade ends as the chip in Grey's head deletes his personality and begins the long process of doing the same to everyone else. It's incredibly grim, yet perfectly on point.
Skyfall
Like most James Bond villains, Raoul Silva dies at the end of this film. Unlike most Bond antagonists, however, he accomplishes his goals before doing so. Silva's real target, behind all the large-scale attacks on MI-6 and the greater intelligence world, is M. Bond's handler betrayed the charismatic maniac years earlier, leaving him disfigured and vengeful. Silva's plan undergoes many steps, some of which go well beyond a simple quest for vengeance.
Seeking M's death is all Silva has left, and he proves that he is willing to destroy anything to achieve that goal. Though he is killed first, M dies of injuries sustained in the conflict. Silva won and didn't even live long enough to celebrate.
The Dark Knight
Christopher Nolan's second take on Batman is the perfect version of the classic "bad guy wins" action film. It's the second part of a trilogy, leaving the third film to bring things back to a happy ending. The villain doesn't win the battle, instead claiming a philosophical victory.
The Joker's plan works on almost all levels. He loses the "battle for Gotham's soul", but he successfully corrupts Harvey Dent and lets Batman take the fall for his crimes. Joker comes out on top far beyond any other fixture of Nolan's Gotham.