Exclusive: The 28 Years Later filmmakers open up about returning to their vision of an apocalyptic UK whose future is rooted in the past—and how that will be expanded upon in the next two sequels.

Rose Leslie sweeps into a pub in rural most Suffolk, a land of hedge-lined winding lanes, thatched houses and luscious green fields.She is wearing patterned floral trousers and a warm jumper, and her ...