BOX OFFICE THIS WEEK 12/21

The 3-D science-fiction epic Avatar opened big in first place at the weekend box office, taking in $73 million domestically and $159.2 million overseas. Director James Cameron's first film since 1997's blockbuster Titanic stars Sam Worthington, Zoe Saldana and Sigourney Weaver in a 22nd century story about a paraplegic ex-Marine sent from Earth to infiltrate an alien race of 10-foot-tall blue people on the distant moon Pandora. The movie was made using motion-capture technology that captured actors' performances blended in with computer animation.

The romantic comedy Did You Hear About the Morgans? opened in fourth place. It stars Sarah Jessica Parker and Hugh Grant as a couple whose crumbling marriage gets a fresh chance when they are sent into the witness protection program after seeing a murder. Oscar buzz-heavy Up in the Air, starring George Clooney as a corporate hit man addicted to the frequent-flyer life as he travels the country firing people for downsizing companies, moved up into the top 10, in eighth place, as it widened to more theaters ahead of its nationwide expansion this week.

    * Last week's top movie, Disney's animated The Princess and the Frog, fell to second place.

THIS WEEKEND'S TOP TEN MOVIES -- DECEMBER 18-20

   1. Avatar, $73 million
   2. The Princess and the Frog, $12.2 million
   3. The Blind Side, $10 million
   4. Did You Hear About the Morgans?, $7 million
   5. The Twilight Saga: New Moon, $4.4 million
   6. Invictus, $4.2 million
   7. A Christmas Carol, $3.4 million
   8. Up in the Air, $3.1 million
   9. Brothers, $2.6 million
  10. Old Dogs, $2.3 million