Instead, he focused on his own fears: nightmares that he had as a child and domestic disharmony. Themes included suburban desolation, homogeneity, and showing hitmen as violent murderers. Wheatley also wanted to highlight current events: unpopular wars, a recession, and erosion of the social contract. The film's story came partially from casting ideas, and Wheatley specifically wrote the part of Jay for Neil Maskell, with whom he'd worked previously on a TV series. Wheatley always had a plan for the ending and made sure the story was logically consistent, though he states that there are multiple possible interpretations and the cult itself remains scarier when its motives and background are shrouded in mystery. Wheatley states that cultists are a popular choice of antagonist because people are uneasy about the world and feel a lack of control and understanding; politicians and bankers who control their lives seem inscrutable. The cult's symbol was designed by Wheatley, who later recognised influence from "The Blair Witch Project". Wheatley was worried people might call him on its similarities, but he was instead surprised to find people comparing it to a symbol from "Harry Potter and the Deathly Hallows", with which he is unfamiliar. The film's most violent scene, the hammer murder, came about when Wheatley was surprised at the shocking violence in "The Orphanage", which he had assumed would be a subtle art-house film. Wheatley stated that this turn toward violent horror in "The Orphanage" made the rest of the film unpredictable; he wanted a similar unpredictability in his own film, so that viewers were never sure whether the film would be subtle or explicit. The song "It Could Have Been Better", used in the film, is performed by Joan Armatrading. It was written by Armatrading and Pam Nestor and is from the 1972 album "Whatever's for Us". The film's North American premiere was 12 March 2011 at SXSW in Austin. It was released to UK cinemas on 2 September 2011. IFC Films brought the film to video on demand 4 January 2012, and it received a US theatrical release 3 February 2012. It was released on home video in the UK on 26 December 2011 and 14 August 2012 in the US. Rotten Tomatoes, a review aggregator, reports that 77% of 87 surveyed critics gave the film a positive review, and the average rating was 7.1/10; the consensus is: ""Kill List" is an expertly executed slow-burn crime thriller that thrives on tension before morphing into visceral horror."