Pretty Poison (1968)

When a mentally-disturbed young man tells a pretty girl that he's a secret agent, she believes him; murder and mayhem ensue.

Director: Noel Black

Cast: Anthony Perkins, Tuesday Weld, Beverly Garland, John Randolph, Dick O'Neill, Clarice Blackburn, Joseph Bova, Ken Kercheval, Don Fellows, George Ryan's Winslow High-Steppers, Jay Barney, Timothy Callahan, Parker Fennelly, William Fort, Tom Gorman, Paul Larson, Dan Morgan, Maurice Ottinger