This week we have been reporting from the Berlin International Film Festival. And without a doubt, very high on the list of favorites has been Undine, the new film from Christian Petzold, the director of Transit, Barbara, and Phoenix. His latest tells the story of a museum guide who tries to move on from a breakup to a relationship with a new man. But there are undercurrents of something mysterious to this romance, which draws on the age-old myth about a water nymph, named Undine. In Berlin, Film Comment assistant editor Devika Girish sat down with Christian Petzold, an inveterate storyteller, to talk about Undine.