Then, of course, you have Fight Club, wherein Tyler Durden, the Narrator, and Marla Singer spend their days in the same house, but all three of them are never shown to interact at the same time, and the movie sometimes resorts to sitcom hijinks to achieve this. The Narrator finds out he is Tyler when Marla refers to him as "Tyler," which she presumably never once did up until that point and is something that can't be hand-waved away by Tyler's "Don't talk about me" rule.
The 2018 Charlize Theron film Tully, which is a lot like Fight Club except with less brawling and more postpartum depression, has a twist that relies on Theron's husband not once thinking to go and see the stranger he's letting into his house at night to look after his newborn child (spoiler: she's imaginary). The TV series Mr. Robot would manage to craft eight episodes' worth of carefully staged interactions before revealing the main character's friend is both imaginary and dead.
It's not like this technique was invented in 1999, either. In Psycho, Mrs. Bates is painted as a loud, intrusive, and controlling old woman, but is only heard when Norman isn't around. She also never talks over him when they're arguing, and never shouts from the house when she knows Norman is with Marion, which is something that kind of person would definitely do if they hadn't already been murdered by their own son.
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