Now how's this for a bit of confidence? Sherlock Holmes, starring Robert Downey Jr and Jude Law, doesn't roll into cinemas until Christmas Day in the US (Boxing Day in the UK), but already Warner Bros has begun work on a possible sequel.

According to a blog at The Hollywood Reporter, the studio has taken in Kieran and Michele Mulroney to pen a screenplay for a second Sherlock Holmes adventure (the pair are responsible for the script of the upcoming Paper Man, and they've worked on the screenplay of Justice League: Mortal for Warner Bros too). The sequel is set to bring Holmes' legendary nemesis Moriarty into the action, too, and the early rumour mill is already linking Brad Pitt with the part. That said, no formal offer or deal is reportedly in place.

Incidentally, Moriarty reportedly appears in shadow form in the film due out this Christmas, and there's been no confirmation that it's Pitt's shadow that's been seen in early footage from the film.

The Hollywood Reporter suggests that most of the original's cast are likely to return for a Sherlock Holmes 2, and that director Guy Ritchie, too, may be back on board.

Given that it doesn't cost too much to get a script up and running, it does seem a prudent move from Warner Bros to get things moving to save time should the original be the success that the studio is hoping for. We suspect, though, that a Sherlock Holmes 2 wouldn't get a formal green light until early next year at the earliest, once the box office tallies have been counted up from Sherlock Holmes 1.

The Hollywood Reporter