New Delhi, July 21 -- James Gunn's "Superman" showed staying power in its second weekend at North American box offices, collecting $57.3 million in ticket sales and remaining the No. 1 movie in cinemas, according to studio estimates Sunday.

None of the week's new releases - "I Know What You Did Last Summer," "Smurfs," and "Eddington" - came close to touching Warner Bros. and DC Studios' superhero success. "Superman" dipped 54% from its domestic opening, an average decline for a big summer film.

In two weeks, "Superman" has grossed $406.8 million worldwide, a good start for the movie DC Studios is banking on to restart its movie operations. A big test looms next weekend, when the Walt Disney Co. releases Marvel's "The Fantastic Four: Fir...