The Nicolas Cage paranormal thriller “Knowing” knew how to take the number one spot at the box office this weekend. The film earned $24.8 million on its debut weekend, according to studio estimates from box office tracking firm Nielsen EDI.

In the film, Cage plays a single-dad scientist whose son somehow channels alien life forms through numbers. It was the ninth film for cage to open in the top position since 1997. Meanwhile, studio executives had similar expectations for Julia Roberts and her film “Duplicity” which also open this weekend. Despite the positive outlook, the movie which co-stars Clive Owen failed to meet those expectations taking more than $10 million less than “Knowing”, good enough for third place with $14.4 million in gross sales.

The Paul Rudd and Jason Segal buddy comedy “I Love You, Man”, which was the third major release this weekend, took in $18 million and grabbed second place. The movie is the third time in the last three years that Segal and Rudd have teamed up for a successful opening weekend at the box office with 2008’s “Forgetting Sarah Marshall” and 2007’s “Knocked Up” cashing in as well.

Dwayne Johnson’s “Race to Witch Mountain” was fourth with $13 million, bringing the 10-day total for the Disney franchise remake to $44.7 million. The graphic novel adaptation “Watchmen” took fifth place with $6.72 million on its third weekend out. Ticket sales were up 12 percent ahead of last weekend. Final figures are due Monday.

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Box Office Grosses
Week Ending March 22, 2009

Rank Title Weekend Total Gross
1 Knowing (2009) $24.8M $24.8M
2 I Love You, Man (2009) $18M $18M
3 Duplicity (2009) $14.4M $14.4M
4 Race to Witch Mountain (2009) $13M $44.7M
5 Watchmen (2009) $6.72M $98.1M
6 The Last House on the Left (2009) $5.92M $24M
7 Taken (2008/I) $4.1M $133M
8 Slumdog Millionaire (2008) $2.7M $137M
9 Madea Goes to Jail (2009) $2.51M $87.2M
10 Coraline (2009) $2.14M $72.9M