"This Is It" is a knock-out of a film, and a wonderful cinematic surprise documenting the final days of rehearsal for Michael Jackson's elaborate comeback tour.

It was a tour that never happened due to the death of the "King of Pop"; a tour complete with enormous set pieces, fireworks on stage, a first-rate band and world-class dancers.

Directed by Jackson's choreographer and collaborator, Kenny Ortega, this remarkable film is a music lover's backstage pass to what really goes on during rehearsals. And — there in the center of it all — we see a surprisingly lucid, hard-working Jackson paying attention to every step and every note.

"This Is It" is not a sad film; nor is it a glossy valentine to the recently deceased pop star. It is instead an intriguing, detailed, get-up-and-dance documentary that celebrates the creative process.