I'm toggling between two stellar documentary series during my free time this holiday break. One is quite old, and the other is quite new.
The World at War is a British documentary series about World War II that aired in 1973-74. I only recently discovered this 26-episode series existed, and was delighted to find it all on YouTube. It's absolutely riveting, even if you know the outcome.
Making a Murderer is a Netflix documentary series that's unbelievable, and unbelievably good. Buy, borrow or steal yourself a Netflix login and watch this one. It's like Serial on television, only better.