American tenor Tom Randle (Jack Twist) (R), and Canadian bass-baritone Daniel Okulitch (Ennis del Mar), perform during a dress rehearsal of the opera "Brokeback Mountain" at the Teatro Real in Madrid, January 24, 2014. When Annie Proulx first published Brokeback Mountain in the New Yorker in 1997, the American writer said she did not suspect the tragic cowboy love story would go on to inspire an Oscar-winning film and even an opera. The doomed romance between two Wyoming sheep herders caught the eye of American composer Charles Wuorinen for its potential as an opera, now set for its global debut in Madrid on Tuesday. Picture taken January 24, 2014 REUTERS/Paul Hanna (SPAIN - Tags: ENTERTAINMENT SOCIETY)