Actress Scarlett Johansson leaves the stage following a question and answer session along with a short presentation of Iron Man 2 to the the thousands of attendees at this years annual Comic Con conference in San Diego, California July 24, 2009.
In the diary, Clark talks about showing Marilyn around Queen Elizabeth's private apartments at Windsor Castle and other "behind-the-scenes" trips.
Clark published excerpts of his diary in 1958, but left the details of one week out. These chapters weren't released until he died in 2002, and will form the basis of the movie.
Parfitt explained: "Once everyone else was dead, Clark had arranged for the missing week to be issued."
British film writer Adrian Hodges has adapted the papers into a script.
