It stars Gunnel Lindblom, Geneviève Page, Laurent Terzieff, and Keve Hjelm.

Brother Carl had its world premiere in May 1971 at the Cannes Film Festival in its Directors' Fortnight section,[2][3] and opened in New York City on August 11, 1972.

[4] Jonathan Rosenbaum of The Village Voice wrote that, "Unlike [Sontag's] thumbless four-finger exercise, Duet for Cannibals, Brother Carl does not fully achieve what it sets out to do, but the scope of its ambition is so much wider that one can find its failure far worthier than the modest success of her first film.

"[2] Sally Beauman, in a review of the film for New York, called it "a strange work"; she criticized its pacing and the characterization of Carl, but concluded that, "the faults do not detract ultimately from the film's worth.

"[5] The New York Times' Roger Greenspun criticized Page's performance but wrote overall that the film "[takes] considerable imaginative and emotional risks, as Duet for Cannibals did not, and the result is a real movie.