Keanu Reeves is the star of 47 Ronin (2013) a movie based on an actual historical event that took place in Japan in the early 1700s. While other characters in the film have been part of the mythos for centuries Keanu’s character—a half British, half Japanese "outcast" and "half breed"— was entirely created by the studio and shoved into the narrative.
Keanu’s character was left out of the film’s climactic fight scene (perhaps because he wasn’t part of the original story to begin with) but the studio seized control of the movie from the director and insisted that more scenes with Keanu be added.
“Universal opted to reshoot a major fight scene near the end of the film, as well as a few other scenes to sharpen the focus on Reeves’ character Kai.
“[Originally,] Kai was not even present in the final battle scene, whereas the new scene pits Kai against a supernatural creature.
“In addition, the studio added a love scene, close-ups and individual lines to boost Reeves’ presence.” [source]