Blinded by the Light (1980)
When teenager David Bowers renounces his home and family to run off with a quasi-religious cult, his sister, Janet, sets out to bring him back, very nearly becoming brainwashed herself.
When teenager David Bowers renounces his home and family to run off with a quasi-religious cult, his sister, Janet, sets out to bring him back, very nearly becoming brainwashed herself.