This highly fictionalized account of the Boston Strangler cases of 1962-1964 has some flashy direction by Richard Fleischer and boasts some great usage of multi images and split screens which is used to show, among other things, roommates going about some mundane household task in one screen while another roommate is shown laying murdered in another.
The film is divided rather neatly into two parts. The first half is a police procedural with a couple of colorful detectives checking out tips and equally colorful possible suspects as the victim count rises. Albert DeSalvo (Tony Curtis) is captured - and for that matter first appears - at the halfway point. The second half consists of a character study and psychological profile of DeSalvo as he is extensively interviewed and questioned by assistant D. A. John Bottomly (Henry Fonda).
The part about DeSalvo having multiple personality disorder as well as how he was caught is completely false, but the anecdote about the psychic was true - A psychic really was employed who gave a completely accurate description of a suspect in the case who also turned out to be totally innocent. This episode greatly embarrassed the attorney general.
Made the same year that the production code officially ended, it dealt with sex crimes quite frankly and in a way that would have been considered unthinkable just five years before. The supporting cast has a deep bench and includes George Kennedy, Sally Kellerman, William Hickey, Hurd Hatfield, Mike Kellin and in small roles people like Alex Rocco and James Brolin. If you can deal with a true crime film that has quite a few falsehoods in it for the purpose of dramatic license, I'd recommend this one.