Thanks to the advent of affordable digital filmmaking, there's been a recent wave of compelling documentary films about lesser-known musicians, performers who never quite made it onto the cultural radar. Two of the best of those documentaries are playing tonight. Malik Bendjelloul's Searching for Sugar Man tells the story of Bendjelloul's attempt to find forgotten Mexican-American singer Sixto Rodriguez, who released a pair of artistically rich but commercially inert records in the early '70s, then disappeared into obscurity -- except in South Africa, where, unknown to Rodriguez, his songs were embraced as anti-Apartheid anthems.
No less astonishing is Hitchcock director Sacha Gervasi's Anvil! The Story of Anvil, which tells the true story of (you guessed it) Anvil, a deeply Canadian heavy metal band that fell off the map after releasing a few genre-defining albums in the early '80s. 20 years and 10 ignored albums later, the band makes one final attempt to break through, resulting in a comedy of errors which even Anvil admits plays out like a real-life, often heartbreaking version of This Is Spinal Tap. Both Sugar Man and Anvil! are paeans to the importance of staying true to yourself and singing from the heart, even if nobody seems to be listening.
Searching for Sugar Man starts at 7 p.m. and Anvil! The Story of Anvil starts at 8:45 p.m. at the Castro Theatre, 429 Castro (at Market), S.F. Admission is $8.50-$11.