As they might say in Variety, this film is a three-hander. Viggo Mortensen, Kirsten Dunst and Oscar Isaac soak up 99% of the screen time. Dunst is barely recognizable as made up. I understand they do this in Hollywood so a famous actor or actress can play a role without overpowering it, but in my experience as a filmgoer, all this does is make you really strain to figure out, "Who is that, really?" Anyway, taking the lazy was out (and insuring that I commit no spoilers), IMDB's capsule description is: "A thriller centered on a con artist, his wife, and a stranger who flee Athens after one of them is caught up in the death of a private detective."
My wife and I enjoyed it. Some reviews have called it boring and tedious, throwing the old "nothing happens" canard at it. Well, we like European movies, and slice of life movies, and this is a slice of life movie set in Europe. The Rotten Tomatoes rating is all over the lot; 82% from critics, 54% from viewers. Go figure. Its already streaming, so you can see it cheaply. It is entertaining and intelligent, a good combination in my opinion.