when did this show first air?
2014.
Inside No. 9
The first series was shown in 2014 and featured six regular episodes and a special online-only episode. 
inside no 9 season 1 episode 4 cast UNANSWERABLE
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Inside No. 9 [SEP] Introduction
In the Comedy.co.uk Awards it was voted "Best TV Comedy Drama" in 2014, 2015, 2016, and 2017, and was named "Comedy of the Year" in 2017 and 2018.