Instead of downloading and parsing available data and reinventing the wheel, I would also recommend using 3rd party free APIs like http://www.omdbapi.com/
Just a thought...
This is what goim does: https://github.com/BurntSushi/goim
There are maybe one or two other tools that can do this, but they are insufficient for $reasons or were too slow for my taste. There is a brief comparison toward the bottom of goim's README.
I update goim in a cronjob every Saturday morning (new IMDb data is updated weekly on Friday, IIRC). It's been humming along without incident for a few years now. :-)