(CNN) "Good Boys" topped the US box office with a $21 million opening weekend, according to estimates by Box Office Mojo.

The raunchy coming-of-age comedy, released by Universal, ran in 3,204 theaters. It is the biggest opening for an original comedy so far this year.

Seth Rogen and his writing and producing partner Evan Goldberg produced the film. It was co-written by Lee Eisenberg and Gene Stupnitsky and directed by Stupnitsky. The story revolves around three 12-year-old boys, played by Jacob Tremblay, Keith L. Williams, and Brady Noon, who are sixth-graders on the hunt for a first kiss.

"Good Boys" had been expected to topple under "Hobbs & Shaw" in North America with an opening in the $12 million-$15 million range. Nearly 70% of the "Good Boys" audience was between ages 18 and 34, according to The Hollywood Reporter.

Universal has also been having a great August box office with "Hobbs & Shaw," which placed second in its third weekend at theaters with an estimated $14.1 million.

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