The multi-award-winning Finnish documentarian Mika Kaurismäki, brother of Aki Kaurismäki (The Man Without a Past), helms the nonfiction work Sonic Mirror -- a protracted exploration of rhythm as one of life's driving forces. Revered drummer Billy Cobham serves as host, taking the audience on a long musical journey around the world and through a myriad of musical genres and styles. Cobham, Kaurismäki, and co. segue from Western concert halls and stages to the music of African tribes performed by Brazilian street children to the distinct music of autistic patients. Along the way, the filmmakers raise serious questions about the function of music as an identifying force, a means of communication, and an emotional release; they also probe the enduring connections between group awareness and self-awareness. The film ultimately builds to a hugely affirming and cathartic expression of music as collective expression that unifies its performers in spirit.