In their buzzy new film, “The Drama,” Zendaya and Robert Pattinson play an engaged couple whose relationship is imploding. With their wedding just a week away, Emma (Zendaya) reveals a shocking secret about her past that sends her fiancé, Charlie (Mr. Pattinson), into a self-destructive spiral of doubt. The stakes are high for these fictional lovers, but the underlying relationship anxiety is relatable: What if you don’t know the person you love as well as you think you do? What if they surprise you, and that surprise is not good? In this episode, Anna Martin, the host of “Modern Love,” asks Pattinson and Zendaya what these questions mean to their characters, and in their own lives.