Audiences were fired up for the first-ever showdown between martial arts legends Jackie Chan and Jet Li as their new fantasy actioner The Forbidden Kingdom opened at number one at theaters across North America. Those in search of laughs powered the starless breakup comedy Forgetting Sarah Marshall into second place with a strong debut of its own. Targeting different audiences, the one-two punch was enough to propel the overall box office ahead of last year's levels by a respectable margin.

Lionsgate scored its first top spot debut of the year with The Forbidden Kingdom which grossed an estimated $20.9M from 3,151 theaters over the weekend. The PG-13 adventure film averaged a solid $6,623 per location and saw much of its support from young male audiences and fans of martial arts movies. In the film, an American teen mysteriously travels back to ancient China and embarks on a quest to free the famed Monkey King. Chan and Li, who each got to play a double role, provided the starpower to pull in paying audiences. Reviews were mixed.

Opening in second place with a solid debut of its own was the raunchy relationship comedy Forgetting Sarah MarshallForgetting Sarah Marshall which grossed an estimated $17.4M from 2,798 theaters. The R-rated pic about a man coping with being dumped by his celebrity girlfriend averaged a commendable $6,201 and played best to adult women. The Sarah bow was below what producer Judd Apatow has seen in the past with his R-rated summer comedies The 40-Year-Old Virgin ($21.4M), Knocked Up ($30.7M), and Superbad ($33.1M). However, it was stronger than the debuts of his latest offerings Walk Hard ($4.2M) and Drillbit Taylor ($10.3M). Since the surprise success of Virgin in 2005, studios have used Apatow's name and resume to market anything he remotely has been involved in.

Sony claimed three of the next four slots. Last weekend's number one film Prom Night crumbled by 56% to an estimated $9.1M and pushed its ten-day tally to $32.6M. A $45M final seems likely.

The Al Pacino crime drama 88 Minutes was rejected by moviegoers and collected only $6.8M, according to estimates, in its opening weekend. The Sony release averaged a mild $3,137 from 2,168 locations and was panned by critics from coast to coast. The R-rated pic opened in numerous other countries around the world last year and was finally dumped into the late spring graveyard in the North American market.

The kid adventure Nim's Island grossed an estimated $5.7M, off 38%, giving Fox $32.9M to date. Sony's blackjack hit 21 followed dropping 48% to sixth place with an estimated $5.5M and upped its cume to $70M.

The Keanu Reeves cop thriller Street Kings tumbled in its second weekend falling 68% to an estimated $4M. With $19.9M in ten days, look for Fox Searchlight to finish with $25-27M. Toon smash Horton Hears a Who declined by just 41% to an estimated $3.5M leaving the year's top film with $144.4M.

Ben Stein's new documentary Expelled: No Intelligence Allowed was a surprise face in the top ten popping into the number nine spot with an estimated $3.2M. Averaging a mild $2,997 from 1,052 locations, the PG-rated film about creationism was aimed at Christian audiences by distributor rocky Mountain Pictures. Expelled was the only film in the top ten to see Saturday sales drop from Friday so a long life in theaters is not likely.

Rounding out the top ten was the George Clooney flop Leatherheads with an estimated $3M, down 52%, for a total of $26.6M.

The top ten films grossed an estimated $78.9M which was up 15% from last year when Disturbia retained the top spot with $13M in its second weekend; but down 17% from 2006 when Silent Hill debuted at number one with $20.2M.