When trying to secure Philip Seymour Hoffman for his cameo his agent claimed he was too busy so Ricky Gervais requested his email address and sent him the following: "Dear Philip, will you please appear in my new film? There is very little money involved as I spent the budget on testicular implants, but don't look upon them as my testicles, look at them as our testicles." Phillip Seymour Hoffman couldn't refuse after that.
Ricky Gervais insisted that Louis C.K. shave off his goatee because he needed to look like a caveman for the opening scene. C.K. was very reluctant but he eventually shaved it off. The cavemen scene was filmed but it was deleted from the main feature, and presented as a short film on the DVD.
Director, writer and actor Ricky Gervais sponsored an online Photoshop contest related to the movie theme by asking contestants to edit known movie posters as if those posters were usually lying to the audience.
The screenplay for this film was featured in the 2007 Blacklist; a list of the "most liked" unmade scripts of the year.
Stephen Merchant: Ricky Gervais's frequent television co-host is the man whom Mark's father attempts to rob.