In the book Grima has no so deep substance, moved by the thirst of power and money, he was confounded at once, (his leading part is that of the murderer which, at the end, will avoid to Gandalf to get dirty hands).

The film gives him one past, a motive, and motivations, feelings and a power which it has not in the text.

And harder is the fall
( Literally as in the figurative).

To return him a bottom of humanity, it is also to make him able of suffering. And it is in this register which Brad Dourif excels.

 

 

 

One can wonder if it was really necessary, but it seems to be his way to work: investigate a role from the inside.
The impact is always the same and his last close-up, closes on this famous small tear, opening the door to all the interpretations......