Watch the French Original instead I rated it 6 from 10 stars as it was not as bad as the previous reviewers made it look like. But obviously I'm the only one in this reviewer group who watched the original Blunderer movie from France called "Le meurtrier" aka "Enough Rope" (1963) and THAT was a 10 star movie IMHO. It's such a shame that Criterion still has not released it in the US.
Being very familiar with "Le meurtrier" and with Patricia Highsmith' novel "The Blunderer", I could compare and recognize scene after scene and can tell that this is a very close remake to the old French film. Then we watched the bonus material and actually kept waiting for the movie director or the stars to mention the older French version, but nobody did (?).
Anyway, it's not a bad remake, because it keeps very close to the novel plot and to the French original movie. I just wish somebody who was interviewed for the bonus material would have mentioned/honored "Le meurtrier" in which Gert "Goldfinger" Froebe plays the book seller Kimmel, Maurice Ronet is Walter, beautiful Russian-French actress Marina Vlady impersonates Ellie, a musician (not a singer) and Yvonne Furneaux is Clara, Walter's Wife. Robert Hossein plays the detective.
Spoiler: Instead of going to a jazz bar, Maurice Ronet goes to a music festival in the last scene. The original was mise en scene by Claude Autant-Lara in Nice at the Côte d'azur/French Riviera. The remake was filmed in New York City, also taking place in early 1960 with very beautiful colors. The cinematographer alone deserves 6 stars for this remake, but I also think that the actors were quite good. Check this out: http://www.imdb.com/title/tt0057303/?ref_=nv_sr_3