Terry Gilliam is the director of the film Heath Ledger was working on when he died. The film is called The Imaginarium of Doctor Parnassus and was scheduled to wrap in about six weeks. Although production was shut down after the death of Heath, the producers want to continue filming, but this time with Johnny Depp in the lead role. According to The Sun, a studio source says that "There is a point in the film when Heath falls through a magic mirror. He could change into another character after that and that is where Johnny would come in. It's a weird, fantasy, time-travel movie so Heath's character could easily change appearance. It would be a poignant moment. Johnny's not working at the moment so everyone is praying he will do it."
I have mixed emotions about all of this. I understand that movies are a business and there are lots of people involved in the making of the film and certain obligations to be met. But, at the same time it just seems too business like that someone dies and then a week later another actor just comes right in a fills the role and it is business as usual. On the other hand, when an actor dies during filming and the script gets rewritten or the film is edited in such a way that the actor is not in it as much seems like a disservice to the memory of the actor and can often lead to a horrible film which just does no one any favors and leaves the world with a crap film as the last piece of film an actor did.
If Johnny did step in, I think the premise is solid and would be a much better tribute to the legacy of Heath than some cut and paste job the editors, director and writers can come up with. It also would allow all the people who are counting on the money from the film to feed their families a chance to continue to do so.