Google TV & Movies DRM on Mint/Ubuntu

Google Play Movies & TV works best under Chrome on Linux, but unless HTML5 is working for you, Flash is needed for playback and DRM Flash playback requires the long since deprecated HAL.

Fortunately an updated HAL is maintained for this purposes. The hal ppa is at:
https://launchpad.net/~mjblenner/+archive/ubuntu/ppa-hal

Most of these details are thanks to Justin Watt at askubuntu.com/questions/166760/how-do-i-play-movies-on-google-play who says:

sudo add-apt-repository ppa:mjblenner/ppa-ha

sudo apt-get update 

sudo apt-get install hal
cd ~/.adobe/Flash_Player
rm -rf NativeCache AssetCache APSPrivateData2