In an epic bungle before 33 million viewers — one that could get his company fired as the Academy of Motion Picture Arts<br />and Sciences’ accountant after 83 years and which robbed “Moonlight,” an all-black, gay-themed film, of its proper moment of celebration — Mr. Cullinan caused the show-business musical “La La Land” to be mistakenly named best picture at the 89th Academy Awards.<br />I’ve shared my personal apology, the firm’s apology, and I’ve begun to talk to them about things we can do to make it right.”<br />The firm declined to make Mr. Cullinan available for an interview, but it later said<br />that once he mistakenly handed out the wrong envelope, “protocols for correcting it were not followed through quickly enough by Mr. Cullinan or his partner.”<br />In keeping with past practice, PwC prepared two identical sets of sealed envelopes before the Oscars show.<br />(As they walked off the stage, Mr. DiCaprio handed her the envelope and said, “Make sure you keep this.”)<br />Next up: Mr. Beatty and Ms. Dunaway, reuniting to mark the 50th anniversary of “Bonnie and Clyde” and announce the best picture winner.<br />Mr. Natoli, the stage manager, was the one who approached Mr. Horowitz, the “La La Land” producer, to see<br />that the envelope he was holding was the spare announcing Ms. Stone’s acting win.<br />But many voices in many kinds of films were honored.”<br />This account of the awards show’s frantic final moments was based on interviews with producers of both “La La Land”<br />and “Moonlight”; academy officials; crew members for the telecast; and PwC executives.<br />“I’m holding the envelope and the award, and I had just given my speech,<br />and there are people on the stage with headsets and I thought, ‘That doesn’t seem right,’” Jordan Horowitz, a “La La Land” producer, recalled.