“Brothers of the Head” is the feverish, mind-bending odyssey of conjoined twins Tom and Barry Howe who were plucked from obscurity by a 1970s music promoter and groomed into a boy band. Grappling with impossible love, artistic rivalry and a dark inner life, the twins embrace their freakishness and spit it back in the form of searing Punk Rock. “Brothers of the Head” is a raucous ride through the seamy underground of 70s rock and an unsettling glimpse into a relationship that is as beautiful as it is destructive.