One of the most influential films ever made, Bergman’s “Seal” is a mesmerizing, apocalyptic allegory whose universal themes and striking beauty — captured in Allen Ekelund’s magnificent black-and-white photography — continue to inspire reverence. Bergman regulars Gunnar Bjornstrand, Bibi Andersson, and Nils Poppe are sensational in supporting roles, while the long-faced Von Sydow makes a perfectly dour, disillusioned knight. With its witches and flagellants, madmen and plague victims, Bergman’s “Seal” is filled with all manner of fascinating images, capped by a dance-with-Death finale you’ll never forget.