Paramount’s controversial Pain & Gain opened top of the North American charts on an estimated $20m and will need to make hay while the sun shines. Marvel Studios/Disney’s Iron Man 3 opens this week and will crush everything in sight.

Michael Bay directed the action comedy starring Mark Wahlberg, Dwayne Johnson and Anthony Mackie as the Miami-based Sun Gym crew.

The film’s depiction of the characters as amiable crooks has incensed those who knew victims of the real-life gang. In recent weeks they have spoken out in the media to describe how the gang carried out kidnappings, extortion, torture and murder. Real-life gang members Daniel Lugo and Adrian Doorbal await execution in Florida.

Lionsgate’s ensemble comedy The Big Wedding with Robert De Niro, Katherine Heigl, Diane Keaton, Amanda Seyfried, Topher Grace, Susan Sarandon, Ben Barnes and Robin Williams arrived in fourth place on $7.5m.

Last weekend’s champion Oblivion slipped to second place and has grossed $64.7m after two weekends. Warner Bros’ baseball drama 42, which cost roughly one-third of Oblivion’s official $120m production budget, ranks third on $69.1m after three weekends.

Roadside Attractions opened Mud, US auteur filmmaker Jeff Nichol’s acclaimed follow-up to Take Shelter, at number 11 on $2.2m from 363 sites. Matthew McConaughey stars.

Overall box office dropped approximately 19% against last weekend and roughly 17% against the same session in 2012 when Think Like A Man held on to its top berth through Screen Gems on $17.6m.

Iron Man 3 kicks off summer season next weekend and stars Robert Downey Jr, Gwyneth Paltrow, Don Cheadle, Ben Kingsley, Guy Pearce and Rebecca Hall.

Estimated Top 10 North America Apr 26-28 2013
Film (Dist) / Est wkd gross / Est total to date

1 (-) Pain And Gain (Paramount) PPI $20m –
2 (1) Oblivion (Universal) UPI $17.4m $64.7m
3 (2) 42 (Warner Bros/Legendary) $10.7m $69.1m
4 (-) The Big Wedding (Lionsgate) Lionsgate International $7.5m –
5 (3) The Croods (DreamWorks Animation-Fox) Fox Int’l $6.6m $163m
6 (5) G.I. Joe: Retaliation (Paramount-MGM) PPI $3.6m $116.4m
7 (4) Scary Movie 5 (Dimension Films/TWC) $3.5m $27.5m
8 (7) Olympus Has Fallen (FilmDistrict) Nu Image $2.8m $93.1m
9 (6) The Place Beyond The Pines (Focus Features) Sierra/Affinity $2.7m $16.2m
10 (9) Jurassic Park 3D (Universal) UPI $2.3m $42m