One of Delon's first big roles and a story that's a spin-off from The Talented Mr. Ripley, there are your two main reasons a film like Purple Noon has somehow remained relevant after all these years. Other than that, it's just a very basic crime thriller that overstays its welcome and doesn't have too much on offer.
Ripley is hired by the rich Mr. Greenleaf to call on his son Philippe in Italy and convince him to return home, in order to take over the family business. Philippe isn't very keen to return home, and Ripley falls in love with the lifestyle of his target. So much in fact that he devises a little plan to turn the tables.
The performances aren't great, the cinematography is rather plain, and two hours is way too long for a simple story like the one on display here. It's not that the film is utterly boring, just a bit too generic. It's not a film I'll fondly remember. If I remember it at all that is. Then again, there's not much that I found actively irritating, so there's at least that.