Not a great movie, but better than average for a small-scale thriller. The Rich Man's Wife lies unforgivably to its viewers. Not a clever, justifiable lie, as in Sunset Boulevard , in which we find out that the narrator is the dead man in the pool. Just a lie. The film is one long flashback as Josie tells her story to the police.
Any final twist becomes arbitrary, lacking meaning.
I didn't tell the ending, but given all the thrillers you've already seen, you can probably guess it. The movie is very film noir in style, without the excessive and un-artful dark cinematography that most modern directors substitute for noir. Berry and the rest of the character-actor cast are fine. Since the gun is a small-calibre weapon, this is more realistic than movies in which people fly over backward if a popgun is so much as pointed at them, but enough already.