Directed by Kirdy Stevens (a pseudonym for Helmut S. Ripperger), Taboo stars the iconic Kay Parker as Barbara Scott. The film is widely credited as the first mainstream adult film to explicitly tackle as its central narrative—hence the title.
The story follows Barbara Scott, a sexually frustrated mother whose friend, Gina (played by Juliet Anderson), attempts to expand her horizons by taking her to a swinger's ranch. Although Barbara initially avoids participating, the experience awakens repressed feelings that lead her to seduce her son, Paul. To her surprise, the seduction is mutual, leading to an ongoing secret relationship. Taboo (1980) - IMDb Taboo 1 1980 Imdb