LOS ANGELES: “Monsters University,” a prequel to Pixar's 2001 hit “Monsters, Inc.,” topped the North American box office for the second straight weekend, figures showed Monday.

The animated movie that tells how monster buddies Mike and Sulley became friends and honed their scaring skills took in $45.6 million from Friday to Sunday, for a total of $170.4 million, said industry trackers Exhibitor Relations.

In second place with $39.1 million was buddy flick “The Heat” starring Sandra Bullock as a talented but haughty FBI agent and Melissa McCarthy as a rough-and-ready Boston cop.

“World War Z,” starring Brad Pitt as a former UN investigator trying to save the world from a zombie invasion, took in $29.8 million, for a total of $123.7 million in two weeks.

Next in the tally was Roland Emmerich's “White House Down,” about a paramilitary group that tries to seize the White House. It garnered $24.9 million in its box office debut.

“Man of Steel,” the Superman reboot starring Henry Cavill, dropped to fifth place in its third week in theaters, with $20.7 million, and a total of $249 million.

“This is the End,” about a group of friends who are invited to a party and become witnesses to the Apocalypse, was in sixth place with $8.7 million.

It was followed by “Now You See Me,” about an FBI agent and an Interpol detective who hunt down a team of illusionists performing bank heists during their shows, which raked in $5.6 million.

The action sequel “Fast and Furious 6,” starring Vin Diesel and Michelle Rodriguez, took eighth place at $2.5 million, followed by “Star Trek Into Darkness” with $2.1 million.

The comedy “The Internship” about a duo of middle aged guys competing with tech wizards after landing an internship at Google, closed out the top 10 with $1.4 million.