Relaxed, witty and fresh off another globe-spanning theater tour, Isabelle Huppert was already slipping back into Cannes mode when we met at Paris’ iconic Lutetia Hotel ahead of the world premiere of Asghar Farhadi’s “Parallel Tales” in competition.

In the Paris-set movie, Huppert stars alongside a powerful cast including Virginie Efira, Vincent Cassel, Pierre Niney, Adam Bessa, India Hair and even Catherine Deneuve. In “Parallel Tales,” Huppert plays a writer in dire need of inspiration for her new novel. She resorts to spying on her neighbors across the street but when a young homeless man (Bessi) gets hired to help her with her daily routine, her reclusive life is turned upside until the fiction she had imagined surpasses the reality of them all.

During a wide-ranging interview, Huppert reflected on the pleasures of mystery in cinema, admitting that when she first read Farhadi’s script, “I thought I didn’t understand everything — and that’s exactly why I wanted to do it even more.” She described the…