Going Berserk (1983)

Chauffeur John Bourgignon (John Candy) is engaged to Nancy Reese (Alley Mills), the daughter of famed Sen. Ed Mills (Pat Hingle). In the midst of a political campaign, Ed -- who disapproves of John -- is blackmailed by a sleazy film director (Eugene Levy) into televising his daughter's wedding. Things go from bad to worse for John when a cult leader, the Rev. Sun Yi Day (Richard Libertini), captures the would-be bridegroom and attempts to brainwash him into murdering Ed.