WELCOME TO MARWEN (2018) 8 p.m. HBO. Fantasy and reality intermingle in this most recent feature from Robert Zemeckis. Based on a 2010 documentary, the film stars Steve Carell as Mark Hogancamp, an illustrator who is the target of an assault that leaves him unable to draw or remember much of his own life. He copes by constructing an elaborate fantasy world populated by dolls in his backyard. The story flits between the real world and the constructed one, which comes alive with the help of distinctive visual effects. The movie, which also counts Leslie Mann, Diane Kruger and Janelle Monáe among its cast, is “at once compulsive in its application of craft and barely in control of its themes and implications,” A.O. Scott wrote in his review for The New York Times. “There is not much in this movie that feels authentic or fully realized,” he added, “but its very strangeness makes it hard to forget or dismiss.”

AMERICAN HORROR STORY: 1984 10 p.m. on FX. Less than a week before the first day of fall, “American Horror Story” is heading off to camp. But don’t come looking for a sunny escape. With previous seasons focused on a coven, a cult and more, the series has developed a following by delivering gory frights. This time the scares are delivered alongside coifed hair and neon swim trunks at a summer camp in the 1980s. It’s a safe bet that the experience will be more “Friday the 13th” than “Wet Hot American Summer.”