Released on her 75th birthday, this celebration of the biggest diva called Ross since Friends showcases her rained-off 1983 concert in New York, AKA the Fire Island Festival AKA Gimme Shelter 2.

Despite the title, Diana Ross: Her Life, Love and Legacy is not a documentary but a concert movie. And even that’s a stretch, considering concert movies usually have some extra material or talking heads (especially in the case of Stop Making Sense).

This is little more than the original TV broadcast, seemingly cobbled together as though someone accidentally deleted the documentary suggested by the title. But as the singer proves in this (unsheltered) Central Park concert, the show must go on, and the event itself is a supreme affair.

Rain check, one, two.

Starting with the concert consumed by a rainstorm, Ms. Ross demonstrates her star power by singing her heart out amidst this torrential downpour in a sparkly orange outfit and cape gusting dramatically behind her, before calmly assuring the crowd that she’d be back on stage tomorrow. The next day, the only chills come from her voice and wetness from her tears as she performs an energetic set spanning her illustrious career.

Her highlights include a dance routine to Maniac from Flashdance, almost “doing a Madonna” by falling off the stage, and an emotional rendition of Billie Holiday’s God Bless the Child that rivals the finale of The Wiz.

At the end of the 1.5 concerts we’ve learnt both nothing and everything about Diana Ross. Not her life, love and legacy but her presence, perseverance and raw talent. So not a documentary, but thanks to Naomi Watts, still the best Diana movie out there.