A sign announces the basement location of Last Exit, a new cocktail-focused bar from the owners of Tonic. (Fritz Hahn/The Post)

You’ll definitely find great cocktails at Last Exit, a Mount Pleasant lounge celebrating its grand opening tonight. It’s located under the Radius pizzeria and accessed via a doorway from Tonic’s basement, but it’s not exactly hidden -- there’s a neon sign in Tonic that says “Last Exit” with an arrow pointing the way. If you didn’t know better, you might think it was some odd Jersey Turnpike reference.

Last Exit is nothing like the Yuenglings-and-wings vibe at Tonic’s new upstairs sports bar: It’s dark, with red lights behind the bar and candles flickering on tables. Walls are exposed brick, seating is a choice of high metal tables or funky old high-backed couches. The soundtrack is more hipster than classic rock. But where the place really separates itself is the cocktails.

Bartender Patrice Hammond is one of my favorite cocktail shakers in the city, and I’ve felt that her talent for playing with infused spirits and fresh ingredients wasn’t put to its best use slinging gin and tonics at Tonic on Friday nights. Here, though, she has her own playground for mixing food and drink. Consider the Harrison: Hammond infuses vodka with fresh rosemary and black peppercorns for a few weeks, which adds a floral quality and a nice hit of spice, then tops it up with tonic for a touch of fizz. It’s a fantastic drink, and it arrives with a tiny Mason jar of green grapes. The fruit is designed to complement the taste of the cocktail and serve as a palate cleanser. Take a sip of the cocktail, then let a juicy grape wash away the taste.

The Olivia is made with tea-infused vodka and served with a side of popcorn. (Fritz Hahn/The Post)

Outside of cocktails, the list of bottled beer is pretty interesting: Weyerbacher’s Simcoe Double IPA, Founders’ Dirty Bastard Scotch Ale, even Rochefort Trappist 10 from Belgium. For special occasions, there’s the rare Utopias from Sam Adams; a 2-ounce pour of this cognac-like elixir will set you back $27. I just wish the draft beer program was more developed. There are six taps, and those beers are available in 4- to 16-ounce pours, a la ChurchKey. But why anyone would order a four-ounce taster of National Bohemian, or who’s going to be unfamiliar enough with Pilsner Urquell to need a flight?

The food is a step up from Tonic’s usual menu: truffled fries, fried chicken livers, even Southwest-style corn fritters.

For a date-spot in Mount Pleasant (or even western Columbia Heights), you’re not going to beat Last Exit right now. It’s only been open for a week, but it’s very promising.

The red-lit shelves behind Last Exit's bar hold a variety of spirits and house-made infusions. (Fritz Hahn/The Post)