The Terminator series has never been clear on how to best utilize its erstwhile main protagonist effectively, but there is a clear reason that Terminator: Genisys’ evil John Connor didn’t work. Reinventing the hero of a franchise as its villain is usually a pretty compelling twist. Making Ellen Ripley into a part-Xenomorph clone, for example, was one of few intriguing ideas in the fourth Alien installment. More broadly, charting a character’s gradual moral dissolution typically makes for engaging viewing. But Terminator: Genisys wasted the narrative opportunity with its evil John Connor twist.

The Terminator movies conclusively proved that the franchise had no idea how to use John Connor when 2015’s reboot Terminator: Genisys made him one of the movie’s many villains. On paper, the prospect of the human resistance leader switching sides and joining Skynet is a dark and interesting idea, but in practice, the twist fell flat with audiences upon the release of the movie. The reason for this failure was rooted in the nature of the Terminator’s franchise villains as morally uncomplicated automatons.

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It’s too late for John Connor to be the star of Terminator 7, but back in 2015 Terminator: Genisys initially appeared to be onto something when it made the hero of the series into the movie’s antagonist. Turning John into Terminator: Genisys’s villain could have been a compelling twist, in theory, but the problem was that the villains of the Terminator franchise are famous for being unthinking, unfeeling androids. As such, John became just another Terminator in disguise and was interchangeable with any of the many shapeshifting villains of the series. The issue was that it didn’t affect or evolve his character in any meaningful way. For viewers to be affected by John’s fall from grace and turn to villainy, it would have needed to come from a change of heart in his character. Instead, his Terminator transformation came about because he was killed by Skynet and his body was repurposed, meaning that whatever new villainy he exhibited had nothing to do with the actual human John Connor as it was merely the shell of his body.

John Connor looking suspicious in Terminator: Genisys

With the twisty, confusing plot of the Terminator movies, with all their timeline retcons, there was ample opportunity to give the real John Connor a valid and compelling reason to betray humanity. Instead, it was a disappointing cop-out. The twist wasn't an authentic revelation or earned development that propelled his story, and the larger Terminator franchise, in a bold new direction. Instead, the reveal simply showed that John had been killed by Skynet—which was bleak, but hardly surprising or worth the viewer’s emotional investment.

Sadly, with Terminator: Genisys ruining the idea on a gimmick, this misfire also likely killed the prospect of a better, more morally complex villainous version of John Connor later in the franchise. While it would be possible for a more subtle movie to focus on John’s shifting allegiance and turn toward the dark side, the fact that the “evil Terminator John Connor” idea has already been tried and tested means it is unlikely to be revisited. Any new Terminator movie reboot will most likely want to drop the Connor family storyline and focus on new heroes entirely. While the Terminator series may revisit the promising idea, fans should not hold their breath after the failure of Terminator: Genisys’ evil John Connor.

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