With no new nationwide event pic on the marquee, Marvel Studios' ensemble superhero pic easily stayed No. 1 in its second weekend. 'Friendship' makes plenty of pals at the specialty box office.

Ryan Coogler's period vampire thriller 'Sinners' also held strong in its fourth week of release, and is soon expected to cross the $300 million threshold.

Will "Thunderbolts" endure at the box office? That's the big question surrounding Marvel's latest big budget tentpole.