Night Swim is a new horror film from Bryce McGuire and producing partners Blumhouse and Atomic Monster. The film was adapted from a 2014 short film of the same name written by McGuire and Rod Blackhurst, though it greatly expands on the concept of the short film in many ways. The biggest difference is that Night Swim the feature introduces a new cast of characters, centering on the family of four who moves into a house with a backyard pool concealing a terrifying secret.

https://screenrant.com/night-swim-movie-kerry-condon-wyatt-russell-interview/