For Single Swingers Only (1968)

"Uninhibited unmarrieds" Gracie and Gloria move into an apartment complex reserved For Single Swingers Only where the bed-hopping' neighbors include studs-in-residence Arty and Dave, "Everybody's playmate" Connie, and Ruth, the lesbian landlady who's also a "peek freak." But not everyone was meant to swing and Gracie starts to crack, especially after finding Arty and Dave making it with a teenage runaway in the living room and Gloria and Ruth doing it in the bedroom: "Everything has an insane, dirty feeling about it" So insane that poor Gracie starts to imagine all the swingers turning into refugees from a horror film.