Alita: Battle Angel features an unfamiliar face. It’s not the lead actress, since audiences have seen Rosa Salazar in Bird Box and the Maze Runner movies. It’s literally the face of Salazar’s character that’s unfamiliar — the giant-eyed CG construct that is the title character of the new film.
Alita may be a bit off-putting at first, but moviegoers have been getting used to this sort of thing for some time now. Developments in visual effects filmmaking have allowed humans to be altered or entirely created via CGI, and the result has almost always been a little off. The feeling this “offness” creates in the viewer is what is known as the uncanny valley.
The uncanny valley occurs when an observer is supposed to recognize a humanoid object as real, but said object comes off as out-of-place and creepy. In the case of Alita, she’s supposed to look somewhat inhuman, but Hollywood has been attempting to create completely realistic people for some time now. Middle-aged actors have been brought back to their twenties while long-dead performers have risen from the grave. “Photorealistic” humans have been created in the computer, and the uncanny valley has often troubled viewers everywhere as a result.
Source: IGN.com 14 of the Best (and Worst) CG Movie Characters