Transformers: The Last Knight will indeed be Michael Bay’s last foray into the world of Autobots and Decepticons, and the conclusion of the series that started with Shia LaBeouf and a little yellow Camaro. But it won’t be the end of the Transformers filmic universe, and Bay says that, because of the questions raised in the final film, there are a lot of directions the franchise could take.

We already know that there will be a Bumblebee movie, and perhaps a Transformers set in the gladiator arenas of ancient Rome, but how much further can it expand? How many more Transformers movies can humanity handle? How deep does this conspiracy go? Bay spoke with Fandango after he finished the final cut of The Last Knight, and said that he and Spielberg have been talking about it.

This is my last of the franchise, so I guess it’s a final chapter in that regard. But the reason I wanted to do a number five … because we had a writer’s room that I kind of asked for about two years ago. We got 12 great writers together and they kind of created a viable way the universe could go. Spielberg and I liked a couple of stories. We merged them together and that’s what created number five… If you watch it closely, there are a lot of ways that this movie [series] can go from here. So it’s basically like a launching board for wherever the series will continue.

So, far from the end of a series, The Last Knight is potentially the branching off point for a ton of different films.

Bay also talked about how difficult it was to shoot that crazy battle sequence featuring Arthurian knights on horses:

I’ve never done a knight battle and I’ve done a lot of action in my life. First of all, it was a very, very, very hard day for me because my dog Bonecrusher passed away the night before. And it was just heartbreaking to try to show up to the set with literally 900 people on the set. And you just had to buckle down and I had literally 70 horses. I had 400 people dressed in full battle gear. It was massive shoot for three gigantic days, but quite fun. And they’ve really got this stuff down in England and ours was a very, very violent, very stunt-filled three days. But very, very well-organized.

Transformers: The Last Knight hits theaters June 21.

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