LA Noire couldn't alter the faces because they were using a tech that was effectively 3D-scanning the actor's head every frame. The result has to look like the actor.
Other techniques (in film) analyze what is shot to plot the individual muscle movements, so they can be applied to virtual muscles on the CG models. An…

Maybe you can thank Andy Serkis and all those other "promote the tech!" videos for helping perpetuate the idea that the capture gets you to the end result, when it's actually an army of artists using reference footage that add the humanity and detail back into it.

This is what happens when you have 2 dozen people working on "you can capture the performance!" instead of 1 animator and a rigger who know what the eff they're doing. Guess which is cheaper and quicker too?

Mission accomplished on the music then, as per the direction given:
Reznor says that Fincher told him to "'think about the really terrible music you hear in massage parlors.' The way that it artificially tries to make you feel like everything's OK. And then imagine that sound starting to curdle and unravel."

I know what happened. You thought it was over when they revealed Amy had set the whole thing up, throwing the pens out of the car window. "There's the twist ending!" you said, "better beat the rush to the urinals" and left the theatre.