Viewers fortunate enough to have seen Canadian queer cinema visionary John Greyson’s Lilies in its 1997 Frameline premiere will remember the foot-stomping standing ovation that greeted this landmark work and its brilliant director. Having received similarly rapturous acclaim for defiantly unclassifiable films such as Zero Patience and Proteus, Greyson once again dazzles the senses and challenges the intellect with his new experimental documentary, a remarkably complex and moving rumination on AIDS activism, St. Teresa of Avila and Gertrude Stein, all plaited into an avant-garde opera featuring a singing albino squirrel.

Greyson intercuts incisive interviews with heroic AIDS activists Tim McCaskell (a tireless crusader against corporate pharmaceutical greed) and Zackie Achmat (whose late-‘90s meds strike brought crucial attention to the need for access to anti-retroviral drugs) with a surreal narrative in which modernist writer and lesbian icon Gertrude Stein abducts the two men to Niagara Falls, where their fictional counterparts sing atonal arias originating from Stein and Virgil Thomson’s Four Saints in Three Acts. Heady stuff, indeed, yet Greyson also finds room for a campy countdown of the Top 100 AIDS Songs, the patron saint of palindromes and an anal analysis of Stein’s “pigeons on the grass alas” wordplay.

Greyson’s radical politics and outré aesthetics are in full flower here: The Queen’s Throat author Wayne Koestenbaum opines from his piano bench, Stein and Thomson leaf through an issue of Vanity Fair, Bono leads a parade of celebrity do-gooders and a candy-colored cascade of pills rain down over the afflicted. Music provides solace, as Greyson’s fantasia on art and activism posits the disarming question: would we need opera in a world without tragedy?