The box office showdown between Greta Gerwig's "Barbie" and Christopher Nolan's "Oppenheimer" all started with a date: July 21.
It's not uncommon for studios to counterprogram films in different genres on a big weekend, but the stark differences between an intense, serious-minded picture about the man who oversaw the development of the atomic bomb and a lighthearted, candy-coloured anthropomorphizing of a childhood doll quickly became the stuff of viral fodder.
