The show's finale, titled "WHERE I REALLY COME FROM," contains what can only be described as the Invincible train scene. The bad news: the lasting memory of the finale may be the darkest and most deranged moment in the entire superhero genre of film or television.
The good news: there's going to be a season 2 (and season 3) of Amazon Prime's hit superhero animated series Invincible.
And that led us to a couple more plot elements we could use - it was something that nobody in 30 years since the movie had asked that question. The idea we came up with was, well, Doc has a second lab hidden away. But it doesn’t, so how does that make sense? If Doc built the DeLorean in that lab, Marty would already know what it was. It’s a great moment, and everyone remembers it, but think about it: We’d already seen Marty go to Doc’s lab. “One of my favorite elements is this one: In the first movie, Marty McFly goes to the Twin Pines Mall, the back of Doc Brown’s truck opens up, and the DeLorean comes out. Gale goes on to talk about Doc Brown and reveals the scientist has a secret laboratory that wasn't featured in the films, but it will serve as a plot device in some of the stories that the comic will tell. One of my big questions is how in the hell Doc managed to make a flying time-traveling locomotive in the old west! That's the story I want to know! I don't know about you, but I always thought that when Doc said he had already been there, that he was referring to his adventures with Marty, but I guess that's not the case. Doc’s already been to the future? We’ve got to show that.'” At the end of Back to the Future Part III, when the Time Train flies away, Marty says, ‘Where you going now, Doc, back to the future?’ Doc says, ‘Nope, already been there.’ I said to John, ‘Well, we’ve gotta pay that off.
We’re trying to make sure none of the fans call us out for screwing up the continuity of it. It picks up right at the end of Back to the Future Part III from Doc’s point of view.” During an interview with THR, Gale and his co-writer John Barber explained: “We were talking about it with our editor, with IDW, and the idea of doing a story about Doc, Clara, Jules and Verne - his whole family - it seemed like a good starting point for a good story. Since Doc has already been to the future, they want to show what that is. Already been there." That is the main inspiration behind the comic. The last line spoken in the clip comes from Doc after Marty asks him if he's going Back to the Future.