Host Luke Burbank and announcer Elena Passarello discuss the mysteries they can never seem to solve; 99% Invisible podcasters Roman Mars & Kurt Kohlstedt unveil the hidden world of everyday design in their companion book “The 99% Invisible City;” writer Shayla Lawson takes the lead role in her new collection of essays “This Is Major,” in which she celebrates black womanhood; and Colin Hay, former frontman of Men at Work, performs an acoustic version of their hit song "Overkill."