The working title for the movie was "A Hard Day's Shopping", a reference to The Beatles' film A Hard Day's Night (1964).
In addition to the many allusions to and quotations from John Milton's 'Paradise Lost', the Chauffer's monologue after he drops Tennant and Lowe off at the concert venue is a misquotation from Milton's 'Lycidas'.
The background music in the Pilot's monologue is 'Nimrod' from Edward Elgar's 'Enigma Variations'