Girls on Film is written in the key of A Dorian.
According to the Theorytab database, it is the 3rd most popular key among Dorian keys and the 32nd most popular among all keys. The A Dorian scale is similar to the A Minor scale except that its 6th note is a half step higher (F♯). Chord progressions in Dorian have a characteristic sound due to the major quality of the chord built on the 4th scale degree.
See the A Dorian Cheat Sheet for popular chords, chord progressions, downloadable midi files and more!