Todd Phillips' latest comedy "The Hangover" topped the North American box office Friday with an estimated $16.5 million in ticket sales.

Starring Bradley Cooper, Ed Helms and Zach Galifianakis, the film follows three guys who lose their best friend (Justin Bartha) during a wild night out in Las Vegas. "The Hangover" is currently playing at 3,269 locations.

At No. 2, Pixar's "Up" collected another $13.5 million, bringing its total gross to $106.5 million after only one week in release. The Pete Docter-helmed animated film follows a 78-year-old as he embarks on an adventure to South America.

Meanwhile, new entry "Land of the Lost" only finished third, scoring $7.2 million from 3,521 locations. Directed by Brad Silberling, the comedy stars Will Ferrell as a crazy scientist who discovers a new dimension filled with awkward creatures.

Shawn Levy's "Night at the Museum: Battle of the Smithsonian" slipped to No. 4 Friday, taking home $4.5 million for a domestic total of $117.2 million. Following in fifth place with $2.5 million was Sam Raimi's "Drag Me to Hell," which lifted its cume to $23.7 million.

"My Life in Ruins," the weeks third wide release (1,164 locations), finished ninth with $1.1 million.

Source: Box Office Mojo (www.boxofficemojo.com)