* Real-life wrestling murder at prestigious 12-day festival
* Steve Carell unrecognisable as Du Pont heir in Foxcatcher
* Cronenberg's "Maps to the Stars" also has Cannes premiere
It is the first time at Cannes for U.S. director Miller, whose 2005 film "Capote" earned him a nomination as Best Director at the Academy Awards and a Best Actor win for its star, the late Philip Seymour Hoffman.
The top-notch cast includes Channing Tatum and Mark Ruffalo as Olympic champion brothers Mark and Dave Schultz, and a cast-against-type and completely unrecognisable Steve Carell as John du Pont, a role Miller said was "far out of his (Carell's) comfort zone".
"My athletes consider me as a brother, a father and a leader," Du Pont boasts during the film after he establishes a training camp for amateur wrestlers on the grounds of his family's sprawling mansion.
But the reality is darker and far less flattering.
An odd character shut inside his world of privilege and surrounded by his mother's (Vanessa Redgrave) equestrian trophies, Du Pont suffers from an inferiority complex.
Yet delusions of grandeur, and a deep-seated assumption that money can buy him anything, see him overstepping his role as benefactor as he clearly yearns to be part of the team - wearing a warm-up suit with his athletes and calling himself their coach and mentor.
Despite the sweat and muscle that are the backdrop, it is a quiet and intensely psychological film that explores the ultimately fatal relationship between du Pont and the two brothers.
"There's a lot of American male repressed non-communication happening in this film," Miller told journalists and critics at a press conference. "There's an undercurrent beneath the undercurrent. Every scene is just the tip of the iceberg."
The real Mark Schultz visited the set during filming.
"Having Mark there was emotionally very intense because he was sort of reliving a difficult time for him," said Ruffalo. "You go through a bad time in your life once and then you have to go through it again on a movie set, that's a little heavy."
As for Carrel, Miller said he had trusted his instincts that the actor lauded for his skills at comedy could handle the transformative role.
Approaching a dramatic role is no different from a comedic one, the actor said: "I don't think that characters in films know that they're in a comedy or a drama, they're just characters in a film."
The prestigious 12-day festival on the palm-lined French Riviera is now in its sixth day. Also due to hit the red carpet on Monday evening were Robert Pattinson and Julianna Moore, stars of "Maps to the Stars" by a Cannes regular, Canadian filmmaker David Cronenberg.
Often called Cronenberg's answer to Robert Altman's scathing attack on Hollywood, 1992's "The Player," the film centres on an aging actress (Moore) and daughter of a famous film star desperate to land a role playing her now-dead mother.
Taken to task in Bruce Wagner's script are a myriad of soft targets that make Hollywood tick - the personal assistants called "chore whores", the daily healing massages, the teenage stars, limousines and agents and the gross self-absorption.
Cronenberg denied that his film was Hollywood-centric, saying its themes of monstrous egotism, callous self-advancement and privilege applied elsewhere.
"You could set this in Silicon Valley, you could set it on Wall Street, anywhere people are desperate, ambitious, greedy, fearful," Cronenberg said. "You could really set it anywhere and still have that same tone and same ring of truth."
Reaction to the film after a Sunday night press screening was mixed. The Hollywood Reporter said it was "a prank more than a coherent take on 21st century Hollywood" and, in a broadly positive review, Britain's Guardian called it "vivisectional in its sadism and scorn".