This place is awesome. Everything is so professional yet quirky and I love it. I could spend like 30 minutes reading the menu because of all the little hidden jokes on it... including their continuously updated plea never to touch their blinds (which, you totally should when they aren't looking, because they are made of cool beads!).
The sushi is all fresh and tasty and very cheap during happy hour (10% off everything, 50% off some rolls).
I am not saying you should mention the word underground to your server but I am not saying you shouldn't either, and if you do you may be rewarded with very delicious menu options...