Sure, everyone knew that tailor-made blockbusters like "Harry Potter and the Transformers Hangover" and "Captain Thor: First Class" were going to dominate the box office during the summer of 2011, but who foresaw that 'Bridesmaids" would be up there too?

The $30 million-ish movie had a surprisingly strong domestic debut ($26 million) and had the long legs to end up with nearly $300 million worldwide. 

 

Here are three reasons why that happened:

 

1. Kristen Wiig

 

Known for her "Saturday Night Live" presence for years, Wiig was second (or third, or fourth…) fiddle in male-centered studio comedies until she co-wrote her way onto the A-list with "Bridesmaids." In a bold, brash performance, Wiig turned in what was probably the funniest leading role of the summer and, along with the rest of the golden cast, elevated "Bridesmaids" above 2011's other comedies.

 


2. The cast camaraderie

 

Wiig has worked with friend and co-star Maya Rudolph for years on "SNL," but the onscreen chemistry reached beyond that. Watching Rose Byrne, Ellie Kemper, Chris O'Dowd Jon Hamm and recent Emmy-winner Melissa McCarthy riff off each other was a blast. Check out this short behind-the-scenes clip for some on-set shenanigans.

 

 

3. People like to laugh

Gross-out gags aside, "Bridesmaids" trafficked primarily in smart, heartfelt humor that sprung from believable relationships between the characters, be they best friends, frenemies, or new lovers. This short gag reel, found on the newly-released DVD, will remind you of all the hilarious bits. On Judd Apatow productions, it always looks like the cast and crew are having as much fun making the film as the audience should be having watching it. 
 

The inevitable sequel won't be out for a while, but in the meantime you'll be able to see Wiig, Rudolph, O'Dowd and Hamm reunite in the upcoming "Friends WIth Kids."