Warner Bros.' superhero actioner "Watchmen" opened Friday in the United States and Canada as Hollywood's first heavily-marketed film in 2009. It is expected to dominate the box office as the only wild opener this weekend.

Cast member Malin Akerman attends the premiere of the movie "Watchmen" at the Grauman's Chinese theatre in Hollywood, California March 2, 2009. The movie opens in the U.S. March 6.

 Many industry observers believe that "Watchmen" could easily surpass the opening gross of box-office phenomena "300," director Zack Snyder's previous film, which took in US$71 million in its first weekend two years ago.

According to Warner Bros., "Watchmen" grossed US$4.6 million in Thursday midnight runs, more than double the midnight gross for "300". Like "300," "Watchmen" is a film adaptation from a popular graphic novel.

Cast member Jeffrey Dean Morgan (L) greets co-star Malin Akerman at the party following the premiere of the movie "Watchmen" in Hollywood, California March 2, 2009.

 The film officially opened Friday morning in a total of 3,611 theaters in North America, the widest release ever for a R-rated film, after it played an impressive 1,600 locations across the United States starting Thursday midnight.

(Xinhua News Agency March 7, 2009)