Who eats at Sushisamba Rio? Tourists in jeans shorts and Cubs shirts. Also: girls from the suburbs, pre-partying in full makeup. And last week: me, there for the first time in whoknowshowlong, to check out the menu that chef Dan Tucker revamped a few months ago. Japanese-Brazilian-Peruvian food is still the restaurant’s peculiar concept, but either because of Tucker’s now-more-segregated menu or because experience taught me to know better, I relegated my eating to one country at a time. Mostly I stuck with Japan, taking advantage of Tucker’s way with his Japanese robata grill. First I had the yellowtail cheeks, the meat coming off the bone in lush, oily chunks. Then I ordered more: a special of bone marrow, to which the grill added a smoky crust, and a simple skirt steak with just hints of the promised malbec butter. Harmless duck croquettes (I guess I was in Peru now?) and boozy caipirinhas were enough to keep my interest between the grilled bites, but when I tasted the tuna tiradito, the fish dressed with yuzu soy and hickory oil, I really woke up. It was, in a word, spectacular. Which makes me think these tourists, et al, are on to something. 504 N Wells St, 312-595-2300.