"The success of 'Once Upon a Time … in Hollywood' proves that in the right hands, both creatively and in terms of the distribution and marketing strategy, an R-rated, almost three-hour-long period drama can have mass appeal and yet maintain its credibility as a true piece of auteur-driven cinema," said Paul Dergarabedian, a senior media analyst at Comscore. "Tarantino created a knockout of a movie that is at once edgy and accessible, violent and funny and at its core is a buddy movie that audiences clearly found irresistible."