Let's get our Hitchcock sighting out of the way, here he is getting onto the train
How Farley Granger and Robert Walker play off each other is fabulous. It is like having a devil and an angel on your shoulder. Bruno, is creepy, and Walker portrays this nicely with his eratic ways.
Personally, I think Patricia Hitchcock steals the show. Her quite yet astute demeanor leads her to figuring out the whole thing in five minutes. In short, her character Barbara is awesome.
This is how I felt about the ending, it just kind of crashed. It was as fast paced as a carousel, but then went off kilter. If there could have been any better way of catching Bruno I would have grabbed at it but instead we get a runaway carnival ride pinching our crisscrosser, and while it all works out for Guy it left with a disappointing conclusion. It was just too hectic and felt like I was having a seizure. For such a strong picture it ended abruptly and seemed incomplete.