A frequently suggested method I see here, for cleaning up a knife like this, is to soak it for a while (a day or two) in mineral oil, then use some #0000 steel wool to scrub the red rust off. The pitting will remain, unless you do some heavy sanding/grinding, but that's not really necessary (purely a cosmetic issue; the RED rust is what needs to come off). Others use a green Scotch-Brite pad in the same manner. I've also cleaned knives like this using WD-40 (soaked in it, wrapped in a paper towel, and sealed in an airtight container for 2 or more days).
From what I see in your pics, I think perhaps the 'film' you have might just be the 'patina' that naturally forms on older, non-stainless knives. If anything is left on the blade for a time (like water, fruit juice, chemicals, anything acidic or salty), it'll leave odd-looking patterns of patina (oxide layer) on the steel. A lot of folks here actually put 'patterned' patina on their blades, using vinegar, fruit juice, mustard (has vinegar in it), etc. Sometimes results in a similar look to your knife.
I'm sure others here will offer more suggestions.
Edited to add:
If the bolsters are heavily scuffed/scratched, I like to use wet/dry sandpaper to clean those up. Start with something like 400/600 grit, then go through 600/800/1000/1500/2000 and polish (with Simichrome, Flitz or some similar polishing paste). That'll bring 'em up to a nice shine again. A small, flexible rubber eraser, such as is used for drafting/drawing, works well as a 'sanding block' for the sandpaper. It'll conform nicely to the contours of the bolsters, so you don't leave flat spots on 'em.