There are sushi shops that pride themselves on hewing to tradition and then there is sushi m (and blessedly Tokyo has room for both). Here there are two counters: the front one where chefs, led by Nakamura Michimasa (formerly of Sushi Shin), serve classic nigiri (hand-formed sushi) but also dishes like hibachi-seared buri (amberjack) seasoned with shiokōji (a condiment made from kōji, the yeast used in sake brewing, and salt).
Working the second counter: the someliers, under the direction of Kimura Yoshinobu (formerly of Narisawa) who prepare sake and wine pairings, which can include some truly rare and special finds (expect to pay around ¥10,000 for the alcohol pairing). Seatings can be booked between 6pm and 8pm and typically last two hours. Reservations for one of 12 counter seats, possible up to three months in advance, are essential.