Expect the blend of GORT-esque world and Sluggs-y gameplay.
You'll get neon lights, trains passing by, flashlights - all kinds of visual gimmickery.
This mission will throw you in, saying "go," without much context and with the aim of finding out what to do. There's actually a lot to be found and done, but almost all of it completely outside of the Thief-established standards, so you will need to think outside the box and not presume things will work as expected. "Experimental" would perhaps be an exaggeration, but it certainly is unorthodox. Also, crates will kill you.
In the end it feels kind of like a demo/Thief-meets-adventure-game short, and unless you really like its specific kind of puzzles, you'll get bored pretty quickly.