'Sherlock Holmes: A Game Of Shadows' Cheat Sheet

After the spectacular success of "Sherlock Holmes" ? $515 million in worldwide ticket sales and a Best Actor Golden Globe win for Robert Downey Jr., both of which were unpredictable accomplishments given the fact that the film arrived in theaters at the same time as James Cameron's "Avatar" ? it was no surprise when Warner Bros. announced plans for a sequel.

To celebrate the arrival of "Sherlock Holmes: A Game of Shadows," in theaters Friday (December 16), here's our comprehensive cheat sheet of everything you need to know about the action-packed, Guy Ritchie-directed sequel.

A New World of Possibilities
Amazingly enough, talk of a "Sherlock" sequel began three months prior to the original's release, when Brad Pitt was rumored to be joining the cast as Moriarty and there were rumblings that it would be shot in 3-D. Neither of those things panned out, but we did eventually learn that the sequel would be filmed in Paris and London and that instead of "Sherlock Holmes 2," the film's title would be "Sherlock Holmes: A Game of Shadows."

Fresh Meat
Early on, we learned that Rachel McAdams' return as Irene Adler was trimmed to a "very small part," which made way for the addition of a new female lead, Noomi Rapace, who originated the role of Lisbeth Salander in Sweden's "The Girl With the Dragon Tattoo." Ritchie summed up her character thusly: "She's a gypsy princess with balls," he told us when we visited the set. "That's what Noomi brings to the table."

The other new addition was "Mad Men" actor Jared Harris, who won the coveted role of the villainous Professor Moriarty. Harris couldn't give us many details about the role when we caught up with him in early '11, but he did gush about the "great fun" he had on set.

Setting the Shadowy Tone
As we started to inch closer to the film's release, we started to see that the sequel was going to be a bit darker via the first official posters, photos and the first full-length trailer. It's not all dark and stormy, of course, since a lot of the fun of the first film was in the whimsical moments between Downey and Law, and Holmes' various disguises, as revealed in this funny clip featuring more of RDG in drag.

When MTV News caught up with the main players recently, Downey assured us the film is a "superior product" and that everyone had gone to great lengths to make it bigger and better. Perhaps Ritchie summed it up best: "All in all, we tried to basically put this film on 'roids."

Check out everything we've got on "Sherlock Holmes: A Game of Shadows."

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