what novels do that movies can't

Nothing in all the motion-picture arts can put you inside the head, the skin, the central nervous system of another human being the way a realistic novel can. The movies are not much better with status details. When it comes time to deal with social gradations, they are immediately reduced to gross effects likely to lapse into caricature at any moment: the house that is too grand or too dreadful, the accent that is too snobbish or too crude.

Which brings us to another major shortcoming of the movies as a technology: they have a hard time explaining... anything. They are a time-driven medium compelled by their very nature to produce a constant flow of images. Three movies have been made from things I've written, and in each case I was struck by how helpless perfectly talented people were when it came time to explain... anything... in the midst of that vital flow, whether it be the mechanics and aerodynamics of a rocket-assisted airplane or the ins and outs of racial politics in the Bronx.

Tom Wolfe
"My Three Stooges"