The Marvel superhero pic tumbled 66 percent in its sophomore outing domestically, compared to a 53 percent drop for DC's 'Superman.'

Marvel’s First Family might not save the day after all. “The Fantastic Four: First Steps” is quickly losing steam in its second weekend, signaling the comic book adventure isn’t connecting at the box office beyond the film’s core demographic of superhero fans.

First Steps," Disney's debut of the rebooted Marvel Comics franchise, continued to outperform the competition for a second straight weekend at the North American box office, industry estimates showed Sunday.