Fighting Tooth and Nail

Somebody once told me that in "Return of the King," Aragorn really came forward and fought tooth and nail.  I'm not really sure what movie or book he read, but it was definitely not the "Return of the King" that I was familiar with, as I certainly did not recall any scenes with Aragorn fighting any sort of tooth or fingernail monsters. If he had, I think the story would have gotten rather silly at that point. Some people just can't keep track of plot lines very well.