From the book.
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THIS COLLECTION OFFERS 15 CRITICAL ESSAYS (by 15 different writers) ON ANNIE PROULX'S short story BBM and it's controversial film adaption by screenwriters....Each essay explores the short story, the film and the sociocultural phenomenon that follwed the release of the motion picture in 2005
The essays adopt both traditional perspectives and postmodern angles, including those of women's studies, queer studies, sexuality studies, ethnic studies and American studies. Many of the essays focus primarily on the film, it's critical reception, it's stars, it's soundtrack and it's cultural implications.
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That's from the back of the book. I've only started to read it.
page 15
Between the publication of Brokeback Mountain in the New Yorker and it's appearance in the collection of Close Ranges, Proulx added an italicized prologue taking place in the mind of Ennis, suggesting he has found some solace in his dreams of Jack Twist and in his relationship to his married daughter.
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Obviously Ennis dreaming about Jack wasn't shown in the film, so the author explains how Ennis may have found a bit of solace in accepting his daughter's wedding invitation... Well it goes into alot more detail drawing parallels with the dream and accepting a wedding invitation.