From the start Jay Delaney overacts, which hurts the movie's believability. It's been shot 40 years from now, and it begins to show. Not in the music, clothing or women's hairdos, but on the way things are shown. The madman is mad from the start. He may somehow get along in a party, but 90% of the time he looks like "a deranged murderer", so it's truly unbelievable the police doesn't get their claws on their prime suspect, well, sooner. Some hints of the psychopath's personality are still there: callousness, lack of empathy, delusions of grandeur, wanting "thrills" at all costs, manipulativeness ("You are my accomplice now" -to Sophie-), and a total detachment from reality. Anne Vernon was the only great actress, she carries her role with grace. Like the scene when he talks Jay around well... not being murdered :)! Jess Hahn as Floyd, his dad, has a nice scene near the end. Before, he's just stereotyped. Like Jay's whole story: too rich, neglected by his parents, only son, very strict/ religious mum, Jay obsessed by her ("Psycho" overtones, anybody?), mix well, and you have yet another pulp fiction. J. H. Chase is no Shakespeare, but from the books I've read from him, I feel R. Gainville could have done better, way better.
Hungarian born Anna Gaël as the starlet Lucille Baller has an on screen time like a video clip, but is pretty much what we all expect to watch, so I guess she's finely casted, right? It's interesting to know through IMDb of course, that she ended up a highly-regarded war correspondent. So much for a change of scenery! "Lise", on the contrary, didn't seem to fly so high (her career as an OSS woman is remarkable, though :)). Photography is very good, like the scene of him opening the windows or the pans of "frivolity in the upper classes" at the happening/ party. The music is obnoxious, but that's part of the idea, so it's fine! The film Floyd produces is as bad as some of the crap we endure on film festivals, so I guess it's a good pun on us "cinema goers" :).
Watch if you are interested in the subject (absurd murderers, and or cinema frivolity) this is fun.
PS: Near the end when he tries to win time, he tells Lise "everything she wants to hear", just like the murderer to his loving wife in "L'Adversaire", the best of class by far. Psychopaths use words as tools, delivering the highest sounding declarations of love without feeling a thing. That is well shown in this odd film.
PS2: From what I've heard the starlet's surname is "Ballu", not "Baller", please IMDb community of native French speakers, help IMDb and us out :)!