Cannot see a large folder

I have long used a Passport with my Mac and my WDTV.
I have a very large folder on it containing c. 350 movies.
Suddenly, I can see that folder listed on my TV, via the WDTV, I can see it on my NAS software, when I plug it into my NAS (ReadyNAS) but I cannot see it at all in Finder, when it is connected via USB to my macbook. I can see all the other folders on it, in Finder

Hello, try doing a first aid check in disk utility, this should clean any issues that you might have with the drive.