Speaking with Screen Rant, Fichtner gave up a few basic details of the character as now written:
I actually play a guy named Eric Sachs in the movie. And then he goes through a few stages in his existence.
Eric Sachs? Never heard of him.
Now, the writer doing the transcription seemed unsure that Fichtner said Sachs, but seing as the name will be a riff on Oroku Saki, the original Shredder, I think it's a very safe bet. What else might it have been, anyway? Sykes? Could I really live in a universe so brilliant that the villain of a Ninja Turtle movie is named after the director of The Plank? I daren't even dream.
This reinvention of Shredder would seem to explains why a non-Japanese actor has been cast in the part – though, actually, the only explanation we ever needed for that was "American studio film."
As well as his comments on "going through changes," Fichtner hinted at more disruption to the Ninja Turtle norm in his other comments on the film:
There is a whole interesting dynamic that happens in the world of Turtles and all I can really say about it at this point while working on it is that the Turtle film, it's not like anything that I remember about the Turtles before. I feel like this Michael Bay-produced movie is just gonna really be something else. I'm pretty excited.
He's hinting, I believe, at the alien ooze that brings about pretty much everything unusual in the plot. Putting the pieces together, it sounds very much like Sachs is going to get ooze-infected as part of his Shredder origins.
Now I know they're not doing a to-the-letter Shredder, I'm particularly curious to see what costume they put Fichtner in, and what excuses and fan-service they come up with to incorporate Samurai motifs.
Ninja Turtles, or whatever they end up calling it, will be in US cinemas next June and UK cinemas next August.