Downey Jr to direct sci-fi

Robert Downey Jr is planning to make his directorial debut and is writing a science fiction thriller he wants to take to the big screen.

After overcoming his addictions to drink and drugs, the 40-year-old star is itching to fulfil his career ambitions.

He says: "I will direct a movie. It's a big pissing contest and I'll be a monster. I'll probably want to direct something I've written: I've got a killer science fiction idea. I've got the story in my head, kind of like Mozart on ecstasy… it's called The New Math and it's nuts, so cool."