In the 22 years since the Mission: Impossible film series launched, we've watched Tom Cruise's Ethan Hunt go on a lot of crazy missions, many of which have seen him being framed or painted in an antagonistic light. But while his methods may be questionable at times, we can count on Ethan to ultimately fighting the forces of evil. However, had Mission: Impossible - Fallout gone a different direction with its story, the sixth entry in the franchise would have seen Ethan actively working to convince people that he was a villain. When recently asked if he could see Ethan evolving into something of an anti-hero or villain, director Christopher McQuarrie revealed the following:
Well, the movie that I pitched had this notion of Ethan assuming the identity of 'John Lark,' this terrorist who he's forced to adopt without the benefit of a mark. That puts him in a situation where he must be a villain in order to achieve his aim. He has to assume the villain's identity and convince others around him that he's the villain, and in doing so, has to do some villainous things. That's what the movie was going to be, and we were gonna take it to its darkest corners. But that's just not where Mission wanted to go. It worked if you didn't have the team and if you didn't have all the other characters. It made it a smaller, more character-driven movie, which is cool, but there was just no room left for where the story wanted to go. I was struggling with the second act of this movie because I was holding on to that idea and trying to take that to its darkest conclusion. When I let that go, the rest of the movie came together.
So deep down in this alternate version of Mission: Impossible 6 that Christopher McQuarrie envisioned, Ethan Hunt wouldn't have actually turned to the dark side, but in order to accomplish his mission, he needed everyone else to believe he'd gone down that path. The problem with this creative approach, as McQuarrie told The AV Club, is that the Mission: Impossible movies are team-oriented, so while this would have made for an interested character study, Fallout (or whatever this iteration of Mission: Impossible 6 would have been called) overall wouldn't have worked. However, McQuarrie noted that he still wants to explore this "entertaining and enticing idea" in a future movie. Mission: Impossible 7 perhaps?
Warning: SPOILERS for Mission: Impossible - Fallout are ahead!
As far as John Lark goes, that boat has sailed for Ethan Hunt, as Lark was a separate individual in Mission: Impossible - Fallout who led a splinter group of the Syndicate. Still, if Christopher McQuarrie returns for another Mission: Impossible movie and finds a way to crack this Ethan Hunt as a villain idea without setting aside the team dynamic, then it could be a good way for this franchise to embark down an interesting, new path, which isn't easy to do after six movies over more than two decades.