Randomly picked this up again after dropping it years ago.
It's really fun!

Exploring the levels and constantly finding new areas, new ways to take out targets is quite addicting. Paris, Sapienza and Hokkaido are the standout locations; Marrakesh is also decent but sadly Colorado is just okay and Bangkok is plain boring - thankfully the quality of the aforementioned levels is high enough to overlook these missfires.

The level design and experimentation is definitely the core of the game but I found myself surprisingly hooked by the presentation and even its admittedly limited storytelling. I think the reason is that it just nails that spy mystery vibe, even though the actual plot and characters are hardly fleshed out.