The book in Colin's house is "In Dubious Battle" by John Steinbeck. It deals with the theme of individuals absorbed into a group which can be driven with a unified, single minded cause.
The street battle scene was shot in London without permission. A call was made to the police informing them of a "riot" in progress. When a lone policeman arrived to investigate the unlikely cause of the complaint he discovered a street littered with body parts and a number of people sporting bloody injuries courtesy of the make-up team. Fortunately the policeman was amused with what he saw and instead of confiscating any equipment he opted to take a few pictures on his mobile phone and leave the cast and crew continue shooting. In the event of the policeman reacting unfavourably to shooting without a permit Marc Price removed the tape and handed it to a crew member then approached the policeman, empty camera in hand, in order to save the footage that had been shot.
The production budget was an astoundingly low £40. Director Marc Price accomplished this by using leftover makeup, free extras and homemade special effects.
Make-up effects for the blinded basement zombies required all actors to have an appliance over their eyes making them blind for real. Actress Sarah Akokhia thought it would be fun to not visit the set before the makeup was applied and only saw the basement at the film's screening over a year later.
Over 100 actors and friends worked for free playing multiple roles to increase numbers of on screen zombies and humans.