Michael Bay's true crime-tale stars Mark Wahlberg, Dwayne Johnson and Anthony Mackie. The film follows three Miami bodybuilders, who get caught up in a kidnap and ransom scheme that starts strong but goes horribly wrong. It's based on a real-life story.
Tom Cruise's sci-fi adventure "Oblivion," last week's No. 1, dropped to the second spot with $17.4 million.
In third place was "42" with $10.7 million. Rounding out the top five were "The Big Wedding" with $7.5 million and "The Croods" with $6.6 million.
The top films of the weekend were:
1. "Pain & Gain," $20 million.
2. "Oblivion," $17.4 million.
3. "42," $10.7 million.
4. "The Big Wedding," $7.5 million.
5. "The Croods," $6.6 million.
6. "G.I. Joe: Retaliation," $3.6 million.
7. "Scary Movie 5," $3.5 million.
8. "Olympus Has Fallen," $2.8 million.
9. "The Place Beyond the Pines," $2.7 million.
10. "Jurassic Park" in 3-D, $2.3 million.
The Associated Press contributed to this report.
