"Iron Man 3" started the summer movie season with a bang by debuting at No. 1 with a whopping $175 million opening, second only to "The Avengers", which debuted with $207 million.

"Pain & Gain", last week's No. 1, fell to second place with a paltry $7.6 million, followed by "42" in third place with $6.2 million.

The top ten:

"Iron Man 3," $175.3M;
"Pain & Gain," $7.6M;
"42," $6.2M;
"Oblivion," $5.7M;
"The Croods," $4.2M;
"Big Wedding," $3.8M;
"Mud," $2.1M;
"Oz the Great and Powerful," $1.8M;
"Scary Movie," $1.4M;
"Place Beyond the Pines," $1.2M