Push past the “Employees Only” sign on the lower level of Chicago’s FieldHouse Jones Hotel, and you’ll find yourself inside an old janitor’s closet. One catch: Only a reservation can guarantee that you’ll be let in.

That's because this former storage space is taking on a new life as an underground speakeasy. The aptly named Janitor’s Closet (312 W. Chestnut St.) is a dimly lit, intimate 15-seater whose on-the-nose decor — with Pine-Sol boxes, cleaning supplies, and mop heads lining the walls — nods to its previous life.

Sole bartender Jef Tate is the mastermind behind an ever-shifting, intricate cocktail menu. A highlight to look forward to? The bar’s “L” series, including The Brown Line (pictured) — a split base of tequila and mezcal with tamarind, pineapple, lemon, and lime juice, topped with a black garlic garnish that you can nibble on between sips.