In “Dune: Part 2,” Paul Atreides (Timothée Chalamet) rallies the Fremen people against the oppressive House Harkonnen, leading to an epic clash that unites characters from across the galaxy that author Frank Herbert first visited in his 1965 science-fiction novel “Dune.” Director Denis Villeneuve’s sequel, which comes out on Friday, March 1, is a complex portrait of a people at war that has already garnered widespread critical acclaim.