Will Smith a 'Legend' at Weekend Box Office

The last man left on Earth in "I Am Legend" took first place at the weekend box office in North America.

Will Smith crushed the competition with a $76.5 million opening for his sci-fi thriller, distributor Warner Bros. said. The Time Warner-owned studio had hoped for an opening in the mid-$40 million range.

It ranks as his best start since "I, Robot," another sci-fi adventure, kicked off with $52.25 million in July 2004. It is also the best December opening of all time, beating the $72.6 million start for "Lord of the Rings: Return of the King" in 2003, the studio said.

Smith, 39, plays a military virologist who has survived a human-made virus that apparently killed everyone else on the planet. Francis Lawrence directed the film, working from an adaptation of a 1954 novel by Richard Matheson. It was originally envisaged as a vehicle for Arnold Schwarzenegger and director Ridley Scott in the early 1990s.

Also new was "Alvin and the Chipmunks," which squealed its way to No. 2 with $45 million, also far exceeding expectations.

The Twentieth Century Fox release combines real actors, led by Jason Lee, with animated renderings of the beloved singing trio. The News Corp.-owned studio said it had would have been happy with a $20 million opening.