A film documenting the creation of John Lennon and Yoko Ono’s seminal album “Imagine,” this doc paints a portrait of collaboration, most effectively through the words of many of the people who were present to witness the album’s genesis. The film also includes never-before-seen footage of the two in partnership, and has some fresh, if not particularly shocking, insights into the nature of their relationship and the creation of the album that largely defined them both.