New York  - The martial arts adventure fantasy Forbidden Kingdom somersaulted to the top of the North American weekend box- office rankings, according to preliminary studio estimates issued Sunday.

Featuring veteran martial-arts genre stars Jet Li and Jackie Chan, the movie portrays a teenager who magically finds himself transported back in time to China, where he encounters two rival warriors.

Forbidden Kingdom took in 20.9 million dollars in ticket sales in its debut weekend from Friday to Sunday. (dpa)