Culled together from footage shot during rehearsals last spring for Michael Jackson's 50-date London tour, this part documentary, part concert film -- which opens today on 3,500 screens (including IMAX locations nationwide) -- shows an agile, passionate and humor-filled entertainer who displays no hints of his coming death on June 25.

See photos from This Is It

While Jackson certainly looks skinny (the 5'9" singer was 136 pounds when he died), he proves to be a flexible and disciplined dancer on stage, and surprisingly nearly as skilled a singer as he was in his prime. Choreographer and filmmaker Kenny Ortega, a longtime MJ collaborator who directed the tour as well as the movie (he also helmed the High School Musical flicks), packs the film with Jackson classics, especially the high-energy recreations of hits "Thriller" and "Beat It," in which the entertainer and his pack of toned back-up dancers follow the exact choreography from the iconic videos (the doc also includes scenes from an irresistible "Thriller" remake that was meant to run during the concert).

See photos of Michael Jackson's kids saying their finale farewell

While MJ's just as eccentric as ever -- he wears sunglasses throughout the already-dark rehearsals, and matches orange jeans with a silver blazer in a way only the 50-year-old Jackson could -- he also shows surprising grit: At one point he admonishes his audio technicians, "it feels like someone's fist is being shoved into my ear," and when a section doesn't go well with his dancers, he scolds, "that's why we rehearse." (Speaking of his back-up brigade, don't miss the hysterical moment when they practice MJ's signature crotch-grab.)

See how Michael Jackson's face has changed

While the film occasionally drags in the last third (it has one too many ballads, and Jackson's earnestness becomes cloying when he discusses the environment), overall it's a highly charged, personal and captivating peek at the last few weeks of a man who certainly didn't look close to death.

-BRADLEY JACOBS

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