Significant Other is a 2022 American science fiction horror film directed and written by Dan Berk and Robert Olsen. The film stars Maika Monroe and Jake Lacy as a couple navigating relationship issues during a backpacking trip in the Pacific Northwest, which takes a sinister turn following a meteor strike that introduces a shapeshifting alien entity .

Ruth and Harry, a couple in a six-year relationship, embark on a camping trip in the Pacific Northwest. During their journey, Harry proposes, but Ruth declines, citing their prior agreement against marriage. The situation escalates when Ruth discovers a blue puddle in a cave and subsequently pushes Harry off a cliff, believing he has been replaced by an alien impostor. The alien, having assumed Harry’s form, struggles with human emotions, particularly love, which it absorbed from Harry. As the story unfolds, Ruth confronts the alien, leading to a series of events that culminate in a broader alien invasion .

Significant Other premiered on Paramount+ on October 7, 2022. The film received mixed reviews; The New York Times described it as “a rich and eventful ride” with engaging narrative elements, while The A.V. Club found it less compelling but acknowledged rewards for viewers who watch it through to the end .​