Based on the real-life experiences of Ed Horman. A conservative American businessman travels to Chile to investigate the sudden disappearance of his son after a military takeover. Accompanied by his son's wife he uncovers a trail of cover-ups that implicate the US State department which supports the dictatorship.

A truly major work, I Don’t Know observes the relationship between a lesbian and a transgender person who prefers to be identified somewhere in between male and female, in an expression of personal ambiguity suggested by the film’s title. This nonfiction film – an unusual, partly staged work of semi-verité – is the first of Spheeris’s films to fully embrace what would become her characteristic documentary style: probing, intimate, uncompromising.