Terminator Salvation originally planned an entirely different ending than what fans got, but that changed due to backlash received by a leaked script. James Cameron's original Terminator movie, released in 1984, still stands as a terrific blend of sci-fi, action, and horror. 1991 sequel Terminator 2: Judgment Day is, in the opinion of many, one of the best blockbuster movies ever made, full of thrilling action, a surprisingly deep and emotionally resonant story, and career best performances by Linda Hamilton and Arnold Schwarzenegger.
By contrast, 2003's Terminator 3: Rise of the Machines was seen by most, at best, as a fun action romp that unfortunately came with the side effect of retconning Terminator 2's seemingly conclusive and dramatically satisfying ending. However, lots of fans hoped that whatever came next would restore the franchise to its former glory. It's been nearly 20 years since Terminator 3, and none of its follow-ups have come close to the first two, and two of them didn't even top the third.
Terminator Salvation was the fourth entry, and on paper, it could've been great. Christian Bale was cast as the lead hot off The Dark Knight, and fans would finally get to spend some extended time in the war-ravaged future. Sadly, the final product was a huge letdown. It's safe to say, though, that the originally planned ending would've left fans with an even worse taste in their mouths. Thankfully, fans ended up getting to weigh in on this ill-advised conclusion before the film had even released.
Terminator Salvation's Original Ending Killed Off John Connor
In the final released version of Terminator Salvation, Marcus Wright (Sam Worthington), a seemingly benevolent human/Terminator hybrid project that had served as a co-lead, sacrificed his own life to save John Connor. John needed a heart transplant to survive, and Marcus offered his. However, the originally planned ending was very different. Instead of Marcus sacrificing his heart to save John's life, John dies of his injuries from the fight with the T-800. That leaves his wife Kate Brewster, future father Kyle Reese, and right-hand man Barnes in a pickle as to what to do. After all, John is the prophesied savior of mankind and leader of the resistance that ultimately defeats Skynet's forces.
So the group takes a drastic step. Instead of telling anyone else John died, they remove his skin, and graft it onto Marcus' cybernetic endoskeleton. Marcus then becomes John Connor, at least as far as anyone outside of that group knows, keeping the fight against Skynet alive and kicking. Interestingly, director McG actually also revealed that a different scripted version of the ending then got extremely dark, with Marcus revealing himself to have been evil along, killing everyone else, and making John Connor the new face of Skynet. There were apparently several versions of the John becomes Marcus ending written, although obviously none of them ending up being used onscreen. Their abandonment all comes down to an unfortunate, or fortunate, depending on one's viewpoint, chain of events.
Terminator Salvation's Script Leaked, Leading to Fan Backlash
In 2008, about a year before Terminator Salvation's planned summer 2009 theatrical debut, a version of the script leaked online. It's not quite clear who did it or why, but the reaction from Terminator franchise fans was both swift and immediate. The negative reaction was of course partially due to iconic character John Connor being killed off, as 2019's Terminator: Dark Fate also received quite the negative response to its decision to actually kill John for real. That wasn't the main source of consternation though. Most of the anger was directed at the John to Marcus swap.
Benevolent or not, Marcus was still at least partially a Terminator. It's vital to both the overall Terminator story and John Connor as a character that he be a non-super powered human leading humanity against machines that have them outmatched in most ways. John's triumph over Skynet is an underdog story, and a testament to mankind's resolve. Turning "John" into a Terminator completely ruins that setup, and having said Terminator lead the resistance just feels wrong on a myriad of levels. The twist found almost no defenders within the fanbase, making the response of scorn and derision almost universal. An imitation, machine John Connor was what nobody wanted, outside of director McG, and oddly enough, star Christian Bale, who loved the idea, especially the darker version.
Terminator Salvation Ultimately Changed Its Ending Out of Fear
Somewhat amusingly, when the Terminator Salvation script leaked, director McG and other people involved with the film steadfastly denied the spoilers it had revealed were real. While various non-disclosure agreements may have prevented him and the rest of the cast and crew from discussing the film's content in detail, they certainly didn't require straight-up lying to fans. Sure enough, it was eventually confirmed that the script leak had been real, and McG was left with egg on his face. Even then, it was denied that the ending would be changed.
Of course, Terminator Salvation's ending did get changed to the Marcus sacrificing himself to save John story detailed above. It would later come out that these changes were indeed made as a direct response to the lambasting the original ending had roundly received from Terminator devotees. Warner Bros., distributor of the film, and its production company Halcyon, were hoping they could head off further issues by crafting an ending fans would more readily accept. While they did do that, it didn't matter much in the end.
Sporting a massive $200 million budget, Terminator Salvation failed to make a profit in theaters, and drew tepid reactions all around. Christian Bale's infamous on-set rant that was leaked prior to release also didn't help perceptions of the film. Two planned sequels were canceled, and another reboot was attempted in 2015 with Terminator Genisys, which also flopped. Terminator: Dark Fate then came along in 2019, and became another flop. Perhaps it's time to let the Terminator franchise rest in peace alongside John Connor. Sometimes one just has to know when it's best to leave things alone.