Review: Natalie Portman is a toxic pop diva par excellence in the eerily provocative 'Vox Lux'

Natalie Portman thrives on extremity. She's never more thrilling to watch than when she veers from naturalism and plunges headlong into artifice, abandoning caution - but crucially, not technique - and embracing wild mannerisms of speech and gesture.

In her best performances she has deconstructed the agony and the ecstasy of life in the spotlight, first in her dual-layered turn as a ballet dancer in "Black Swan" and more recently in her extravagantly emotional portrait of Jacqueline Kennedy in "Jackie."

But Portman has never explored the darker side of celebrity as provocatively as she does in "Vox Lux," a mesmerizing brew of pop-star psychodrama and cultural history,