Sheer glamour, with Kelly and Grant as the type of people you seldom meet in real life. It has the kitsch traveloguey feel of films of the era, and the big set-piece at the end is disappointing; by far the most interesting moment is Kelly's equation/come-on, as fireworks explode outside their darkened room, of theft with rape.
One of Hitchcock's trifles: even the characters seem to be having too much fun to bother moving the plot forward in any speedy or plausible way, and Hitchcock (perhaps wisely) trusts that you'll be too busy looking at the scenery and listening to the flirting to care. But Hitchcock made many trifles, and not all are as fun. Sadly, points are deducted for the scene where Cary Grant casually slaps a woman. 3 stars.
The level of detail on the new Blu-ray is just staggering. It's honestly like looking through a window into the 1950's. As for the movie itself, I found it only mildly diverting. I like my Hitchcock protagonists to be psychologically tormented ("Vertigo," anyone?) so it's not a great surprise that the film failed to capture me. "To Catch a Thief" is as light as confetti...but at least as much fun to look at too.
Hitchcock takes a vacation and decides to shoot a film along the way. Sure, it's an effortless romp, charming and affable, full of great moments and a feeling of definite immersion (as we experience the caper as a co-conspirator), but it's also Hitchcock experimenting with form; using the script as an excuse to play with colours, sounds, light and movement.