LOS ANGELES — A pair of good-natured monsters overcame Superman and a zombie apocalypse at theaters over the weekend.

Disney's "Monsters University" topped the box office, opening with $82.4 million in ticket sales. The animated prequel reunites Billy Crystal and John Goodman and their characters from 2001's "Monsters Inc."

Paramount's Brad Pitt zombie thriller "World War Z" exceeded expectations to open in second place, forcing the "Man of Steel" to settle for third.

The top 20 movies at U.S. and Canadian theaters Friday through Sunday, followed by distribution studio, gross, number of theater locations, average receipts per location, total gross and number of weeks in release, as compiled Monday by Hollywood.com, are:

1. "Monsters University," Disney, $82,429,469, 4,004 locations, $20,587 average, $82,429,469, one week.

2. "World War Z," Paramount, $66,411,834, 3,607 locations, $18,412 average, $66,411,834, one week.

3. "Man of Steel," Warner Bros., $41,287,206, 4,207 locations, $9,814 average, $210,078,153, two weeks.

4. "This Is the End," Sony/Columbia, $13,290,642, 3,055 locations, $4,350 average, $58,082,166, two weeks.

5. "Now You See Me," Lionsgate/Summit Entertainment, $7,876,002, 2,823 locations, $2,790 average, $94,456,978, four weeks.

6. "Fast & Furious 6," Universal, $4,930,685, 2,417 locations, $2,040 average, $228,618,155, five weeks.

7. "The Purge," Universal, $3,587,630, 2,201 locations, $1,630 average, $59,604,075, three weeks.

8. "The Internship," Fox, $3,400,361, 1,916 locations, $1,775 average, $38,339,866, three weeks.

9. "Star Trek: Into Darkness," Paramount, $3,166,709, 1,565 locations, $2,023 average, $216,777,625, six weeks.

10. "Iron Man 3," Disney, $2,212,582, 924 locations, $2,395 average, $403,157,804, eight weeks.

11. "The Bling Ring," A24 Films, $2,001,903, 650 locations, $3,080 average, $2,343,144, two weeks.

12. "Epic," Fox, $1,793,375, 1,994 locations, $899 average, $101,048,500, five weeks.

13. "After Earth," Sony/Columbia, $940,031, 1,166 locations, $806 average, $57,382,240, four weeks.

14. "Before Midnight," Sony Pictures Classics, $901,292, 441 locations, $2,044 average, $4,618,935, five weeks.

15. "Much Ado About Nothing," Lionsgate/Roadside Attractions, $735,422, 206 locations, $3,570 average, $1,207,853, three weeks.

16. "The Hangover Part III," Warner Bros., $717,304, 530 locations, $1,353 average, $110,013,772, five weeks.

17. "The Great Gatsby," Warner Bros., $602,410, 362 locations, $1,664 average, $141,600,513, seven weeks.

18. "The Croods," Fox, $503,900, 324 locations, $1,555 average, $183,566,525, 14 weeks.

19. "Raanjhana," Eros Int'l, $414,211, 102 locations, $4,061 average, $414,211, one week.

20. "The East," Fox Searchlight, $365,101, 195 locations, $1,872 average, $1,208,042, four weeks.