Sherlock Holmes has a new mystery on his hands that even he and Dr. Watson may not be able to solve.  Why did their new movie, "Sherlock Holmes: A Game of Shadows," massively underperform at the box office this weekend?  Could it be related to "Alvin and the Chipmunks: Chipwrecked" similarly disappointing debut?  Or, to the weeks of surprisingly low openers including "Happy Feet Two," "Immortals," "New Year's Eve," "Jack and Jill" and "Tower Heist"?  Even the world's greatest detective may have a hard time solving this perplexing paradox.

The first "Sherlock Holmes" debuted on Christmas Day in 2009 and found itself with an impressive opening weekend take of $62 million.  Two years later, the sequel opened the weekend before and grossed just $40 million.  "Holmes" may be suffering from a large part of its audience spending their time shopping at the mall for the holidays, but that likely would have explained a less significant dip (the studio was expecting a $50-55 million debut).  Warner Bros., which is already reeling from a disastrous debut for "New Year's Eve" last weekend, will have to hope ticket sales spike during the Christmas through New Year's Eve week.  International may also be responsible for keeping the franchise's legs alive.

Showing signs of audience fatigue in second place was "Chipwrecked."  The third "Alvin" film in five years, 20th Century Fox's cash cow only grossed $23.5 million. The last "Chipmunks" picture, "The Squeakquel" in 2009, debuted to $48.8 million.  20th Century Fox will also have to hope it can sail past "The Adventures of Tintin" over the holiday frame to a gross somewhere in striking distance of the last installment's $219 million domestic take.

Debuting on just 425 IMAX screens was critic's darling "Ghost Protocol."  The fourth "Mission Impossible" film grossed $13.6 million for an eye-popping $30,588 per screen.  Granted, that's largely because of more expensive IMAX ticket prices and a little boost from "The Dark Knight Rises" prologue playing in front of "Protocol."  The action flick expands nationwide in conventional theaters on Wednesday, Dec. 21.  At this early stage, the Brad Bird thriller should easily surpass "Mission Impossible III's" $134 million gross in 2006 and Paramount, as well as Tom Cruise, appear to have brought a franchise back to life.

The disappointing "New Year's Eve" found another $7.4 million for $24.8 million in just 10 days.  "The Sitter" rounded out the top five with another $4.4 million and $17.7 million so far.

"Young Adult" expanded to 986 for $3.6 million for the weekend and $4 million in 10 days.  The $3,702 per screen has to be a big concern for Paramount.



In limited release, Roman Polanski's "Carnage" had an OK debut in five theaters with $85,700 or $17,140 per screen.  Much more impressive was the second weekend of "Tinker Tailor Solider Spy."  The critically acclaimed spy thriller was overlooked by SAG and the Golden Globes, but it still grossed an impressive $452,000 or $28,200 in just 16 theaters.  In 10 days, the Tomas Alfredson flick has $852,000 so far.

New releases this week include the wide release of "Mission Impossible: Ghost Protocol,""The Adventures of Tintin," and "The Girl with the Dragon Tattoo" on Wednesday.  "We Bought a Zoo" debuts on Friday and "War Horse" and "The Darkest Hour" debut on Sunday, Christmas Day.

Look for final box office results on Monday.