Time was, Hollywood filmmakers would regularly travel to China in support of their movies, attending premieres and holding Q&As to drum up buzz in the massive box office market. The pandemic halted that ritual — until this week when Christopher Nolan became the first major Hollywood filmmaker since Covid to stroll a red carpet in China as his Oppenheimer was premiered at Universal Studios’ CityWalk IMAX theater in Beijing, followed by a stop in Shanghai for more screenings and fan interaction.