The album was conceived as a return to the Beatles' earlier, less complicated approach to music. It was recorded and projected for release (under its original title of Get Back) before their album Abbey Road (1969); for this reason, some critics and fans, such as Mark Lewisohn, argue that Abbey Road should be considered the group's final album and Let It Be the penultimate. Rehearsals began at Twickenham Film Studios in January 1969 as part of a planned documentary showing the Beatles preparing to return to live performance. A project initiated by Paul McCartney, the filmed rehearsals were marked by ill-feeling, leading to George Harrison's temporary departure from the group. As a condition of his return, the Beatles reconvened at their own Apple Studio, where they completed the recordings with the help of guest musician Billy Preston.