We got a glimpse of ''Sherlock Holmes: A Game of Shadows,' back in January, thanks to an E.T. set visit, but the first official, high-quality trailer has just debuted on iTunes and yes, Robert Downey, Jr.'s in drag. My, what a lovely bonnet!

Holmes tells Watson (Jude Law), "I'm knee deep in the single most important case of my career," a case that leads him to Professor Moriarty (Jared Harris), a gypsy fortune teller (Noomi Rapace) and, naturally, donning a disguise as a woman. "I know it's not my best disguise, but I had to make do," he explains to a skeptical Watson.

There are snowy battlefield scenes, a lengthy train sequence, lots of explosions and threats from Moriarty.

See the trailer after the jump.