Originally written to consist of six episodes, there was so much footage shot for the second and fifth episodes that they each needed to be split into two parts.
There are numerous references to the Lord of the Rings film trilogy: A massive vinyl banner can be spotted throughout the series, Ezra wears a Weta Workshop hat, and the title of the finale is 'Ever On' which is derived from the song "The Road Goes Ever On."
Most of the otherworldly/unnatural sounds in the series are performed by writer/director David Coupe and altered in post-production.