Penny Bright & Jimmy Witherspoon (1967)

Nelson sets minimal, repetitive imagery against a looping recording of his daughter Oona, which goes gradually from sweet to curious to mysterious to cacophonous as the loops overlap each other. Since its premiere alongside The Great Blondino and other shorts in April 1967, the film has rarely been seen. It stands out as a more textural piece from Nelson, which, rather than retreating into pure abstraction or bland trippiness, subtly transmits an undercurrent of its ominous source material. —Mark Toscano