According to the Sun-Times, Hefner took a liking to the actor after seeing the recent hit film "Iron Man," admiring his humor and skill in showing his vulnerability.
Downey, the son of '70s independent filmmaker Robert Downey, played Charlie Chaplin in director Richard Attenborough's 1992 film "Chaplin." A representative for the actor told the Sun-Times that Downey is interested in the Hefner project but is unlikely to commit to it until a script is done and a director is named.
The project was announced last year with director Brett Ratner, who had directed the three "Rush Hour" films, but Ratner is no longer attached to the project. Brian Grazer, who was a producer on the 2005 documentary "Inside Deep Throat," is among the film's producers.
Hefner was portrayed by Cliff Robertson in Bob Fosse's 1983 film "Star 80" about the life and death of 1980 Playmate of the Year Dorothy Stratten.