Edgar Wright was originally skeptical of casting Nick Frost in the role of Mike. At the time, Frost was a waiter with no prior acting experience. In fact, the character of Mike was born out of Frost making Simon Pegg (his flatmate) laugh, and Wright later said that Frost was brilliant in the part.
As they were making a documentary about the series, Jessica Hynes, Simon Pegg, and Edgar Wright were looking around the "Spaced house", and one of the people who lived there came and told them that there were Spaced fans outside taking pictures of the house. As a joke, Simon and Jessica went outside and said "Are you taking pictures of our house?" The fans just stood there for a few seconds, stunned. In good nature, they chatted and then posed for photos.
Channel 4 commissioned a second season before the first season was even broadcast.
Pegg and Stevenson originally pitched the show as "a cross between Les Simpson (1989), X-Files : Aux frontières du réel (1993), and Bienvenue en Alaska (1990)".
The part of Twist was created specifically for Katy Carmichael. Carmichael said she was loosely based on a friend of hers and Jessica Hynes' from university.