On July 18, 2008, he appeared in "The Dark Knight" as Sal Maroni, a Gotham City Mafia boss who hires The Joker to kill the titular superhero and a renegade mob accountant. Considered one of the best films of its decade and one of the best superhero films of all time, the film received critical praise for its screenplay, visual effects, musical score, themes, performances (particularly Ledger), cinematography, action sequences and direction. The film also set numerous records during its theatrical run. "The Dark Knight" appeared on 287 critics' top-ten lists, more than any other film of 2008 with the exception of "WALL-E", and more critics (77) named "The Dark Knight" the best film released that year. With over $1billion in revenue worldwide, it became the fourth-highest-grossing film at the time, and highest-grossing film of 2008; it also set the record for highest-grossing domestic opening with $158million, a record it held for three years. At the 81st Academy Awards, the film received eight nominations; it won the award for Best Sound Editing and Ledger was posthumously awarded Best Supporting Actor. In 2020, the film was selected for preservation in the United States National Film Registry by the Library of Congress for being "culturally, historically, or aesthetically significant".