A newly engaged couple, Brad and Janet, find themselves stranded with a flat tire during a storm. Seeking help, they discover a nearby castle and decide to knock at the door. Inside the castle, they encounter a group of eccentric characters led by Dr. Frank-N-Furter, a self-proclaimed "sweet transvestite" from the planet Transsexual in the galaxy of Transylvania. Frank-N-Furter reveals his latest creation, Rocky, a physically perfect man brought to life to serve as his companion. As the night progresses, Brad and Janet are drawn into the bizarre and hedonistic world within the castle, experiencing events that challenge their understanding of normalcy and sexuality.

Throughout their stay, Brad and Janet witness a series of strange and theatrical events involving the castle's inhabitants, including the servants Riff Raff and Magenta, and the seductive Columbia. Tensions rise as the couple grapples with their feelings and the increasingly outlandish scenarios they are pulled into. The castle becomes a conduit for exploring themes of freedom, exploration, and identity, culminating in dramatic confrontations and revelations. The night ultimately takes a turn that leaves Brad and Janet forever changed by their surreal adventure, hinting at broader existential questions while maintaining a tone of irreverent celebration.