Here is a short video filmed inside a 'kaiten-zushi' restaurant in Shinjuku, Tokyo during my latest trip to Japan last summer. This concept, known in the West as 'sushi bars' or 'conveyor belt sushi', offers to sit around the kitchen while the chefs prepare small plates of sushi, sashimi and maki.
Most of the time, in Japan, plates that turn around the conveyor belt represent only a small part of the (seasonal) menu. It is customary to order some kind of sushi directly to the sushi chef who 'cooks' it very quickly and with an impressive mastery.
Kaiten-zushi are popular restaurants where you can eat good fish for a reasonable budget. But sushi is not the basis of Japanese food, contrary to popular belief. It would rather be 'ramen' (noodle soups).
In the following video, I translated a few interventions to help the understanding.