What do sourdough bread, the next Star Wars prequel, and Donald Trump have in common? All three revive a feeling that is as old as the world itself, but still very potent: nostalgia. Multifaceted, personal or collective, poetic or reactionary, nostalgia is a complex emotional state. Based on her own very personal memories, the director draws a line from the past to the present and gets to the bottom of the mystery of “nostalgia.”