(Las Vegas) Martin Scorsese unveiled the first images of Killers of the Flower Moon at CinemaCon in Las Vegas on Thursday, his new dark western, where Leonardo DiCaprio plays a serial killer targeting Oklahoma Natives to steal their oil .

Set in the 1920s, this feature film traces the woes of the Osage nation, holder of a land rich in black gold and suddenly victim of mysterious murders and disappearances.

The trailer, shown during the High Mass of Movie Theater Owners in Las Vegas, features Leonardo DiCaprio as Ernest Burkhart. This man in love with an Aboriginal (actress Lily Gladstone) finds himself embroiled in a conspiracy hatched by cattle tycoon William Hale, played by an oil-hungry Robert De Niro.

The film thus allows Martin Scorsese, 80, to associate two of his favorite actors for the first time. A duo investigated by an FBI agent tasked with elucidating the murders, played by Jesse Plemons.

With this love story tarnished by greed, the American cinema giant wanted to explore the motivations behind the murder of the members of this indigenous nation.

The director wanted to show how some Americans “have been able to rationalize violence — even against those they love — by simply saying, ‘This is civilization. One group comes in and another goes out,” he explained.

The film tackles “a forgotten part of our past,” said Leonardo DiCaprio, who was originally slated to play the FBI detective but chose to play the murderer after spending time with members of the Osage nation.

The film was shot on the actual locations of these macabre events. The script was reworked until the last day of filming, explained Mr. Scorsese, who was keen to “do the right thing for them”.

“It was about immersing yourself in this world,” insisted the New York director, despite the heat and the coyotes prowling the Oklahoma prairies.

Killers of the Flower Moon is due to premiere at the Cannes Film Festival in May, before hitting theaters in October.

Initially produced by the Paramount studio, this pharaonic project – lasting three and a half hours, and a budget of 200 million dollars – was bought by Apple, which accepted a true release in dark rooms, before to make it a loss leader for its broadcast platform, Apple TV.

“I’m really excited to have a wide theatrical release before the film is available at home, which is okay…” Mr. Scorsese insisted.

Produced by Netflix, his previous film, The Irishman, had only enjoyed very limited cinema distribution before landing online.

The director of Taxi Driver, Raging Bull and Goodfellas took advantage of his visit to Las Vegas to ask theater owners to include “real auteur films” in their programming, alongside the blockbusters that flood the American market.

The CinemaCon organization gave him a lifetime achievement award. His work “will be revered for centuries and generations,” praised Leonardo DiCaprio.

The last day of CinemaCon was also marked by a surprise appearance from Rihanna.

The singer had come to promote a new animated film on the universe of the Smurfs, in which she will double the famous Smurfette. The cartoon is due out in 2025.

“Hopefully this will earn me some cool points with my kids one day,” the singer joked.