Since humans are mostly made of water, and fish traditionally inhabit water, fish should naturally occur in the human body. Fix this gap in nature’s logic with today’s Groupon: for $20, you get $40 worth of food and drink at Izumi Sushi, located in the West Loop. Today's Groupon is only available for dine-in, and a reservation is required to redeem.

An airy, stylish dining area and full bar sets the stage for Izumi's contemporary Japanese cuisine, offering a colorful spread of both raw and cooked fish dishes on its menu. One of the friendly, attentive servers can kick off your fish-fest with the wasabi mayo potato salad ($5), a combo of mashed potatoes, crisp cucumber, and zesty izumi wasabi, or the seared tuna tataki ($10), which sears its titular thick red fish in tangy lime soy sauce and arrives bejeweled with avocados. Prepare your digestive fishing nets for the magnificent maki, Izumi's signature dish. The succulent strawberry maki ($15) celebrates another successful fruit-fishing season, sporting a super-white tuna and crunchy tempura center layered with spicy tuna and slices of strawberry. Fried prawns and cucumber center the dragon roll ($14), which comes drizzled with mayo and glazed with eel sauce, while the Pacific Surf maki ($12) hangs 10 on your tongue with its blend of Hawaiian yellowtail, jalapeño, and cream cheese topped with tempura crumbs. This Groupon is also good for drinks, such as the sake, which you can order alone ($12–$25) or genetically fused with other spirits to form various sake flights and saketinis ($8–$15). The restaurant also allows patrons to bring their own wine, with no corkage fee added.

"Izumi" translates to "spring water" in Japanese—the restaurant reflects this with its indoor wall of water, flanked by exposed brick walls and high ceilings that generate a relaxed ambience. You can choose to dine in the well-lit bar in front, a pleasant outdoor area for sun-kissed sushi, or spacious back room for clandestine maki poker. Use Izumi's convenient Randolph Street location as a launching pad for late-night drinks downtown or the first raw fish rocket.

Reviews

Metromix gives Izumi Sushi four stars, and Yelpers give it 3.5. Take a look at what the Chicago Tribune's Sushi Scouts have to say:

• Sundays, the urban-hipster edge of Izumi (meaning "spring water") relaxes into a spa-cool vibe that will help you mend your wicked weekend ways. Need an eye-opener? Izumi offers premium sake flights and a dozen martinis ($5 Sundays-Thursdays). Saketinis not your style? Try the Drunken maki ($11), brimming with tuna, salmon, yellowtail, lump crabmeat, lettuce and masago, drizzled in a light, tantalizing Thai mayo that left my lips tingling. – Heather, Chicago Tribune
• Izumi -- "spring water" in English -- features raw and cooked seafood, with a focus on items prepared in the open sushi bar. The narrow space is subdued, with a custom-made fountain showcasing the Izumi logo, sleek white banquettes, a funky paper-lantern chandelier and an antique kimono as wall art. – Metromix
• I was really impressed. It's nice to have a bartender with the knowledge of the food as well as the alcohol she is serving. She helped us order some rolls and nigiri that were perfect and hand picked martinis to our own taste. – interiors, Metromix