Is it a cafe? Is it a gin den? Tonic Lane shows off its two-in-one charm.

At five o'clock every day, a bell rings out through Tonic Lane, heralding its changeover from funky cafe to jazzy gin bar.

It is a bold transition to pull off every night, but while the industry is littered with examples of fusion done badly, Tonic Lane's "unrehearsed" approach is part of its drawcard, co-owners Lain Tapsall and Julian Brenchley say.

The "coffee by day, gin by night" concept came to fruition over copious coffees at Bourke St Bakery's Neutral Bay cafe next door, where Tapsall used to work and Brenchley was a regular customer.

"I only drink gin and coffee," Tapsall says, explaining the genesis of the idea. "And I couldn't understand why no one was doing just Australian gin."

Given their backgrounds, it wasn't long before they were talking business, she says, and their "ginoteria" concept became a reality.

For first-timers, the two have a formidable skill-set behind them. Tapsall has worked in hospitality for more than two decades, while Brenchley is a resident architect on Channel Nine's The Block with a raft of experience designing and fitting out cafes.

"I am the atmosphere and he is the vision," is how Tapsall sums up their oddball partnership.

Tucked in cosy laneway space, Tonic Lane is barely a week old when we arrive on a Saturday evening. Outdoor heaters keep al-fresco customers toasty, but we opt for a more discreet table inside. By 7pm the place is abuzz, with waiters ferrying intriguing cocktails to all corners of the dimly-lit bar.

The aesthetic is best described as vintage milkbar meets quirky wine bar. The kitschy interior hotch-potch includes a retro popcorn machine, a comical clock and bowling shoes. There is plenty of beer and wine, but really, you're here for the gin, with 33 options from 23 Australian distilleries, including Sydney boys Poor Toms, Archie Rose and Young Henrys. 

Tonic Lane's signature cocktail list, The Dirty Seven, pays homage to Tapsall and Brenchley's past. The Gin Train, for example - served deconstructed on a board with champagne, maraschino liqueur and a sprig of rosemary - recalls the time Tapsall was busted carrying a bottle of Bombay gin on the train. 

The Salty Dog is a refreshing hit of Bass and Flinders gin with grapefruit juice, ginger, lime and cinnamon stick garnish. The delightful Naughty Sally uses Archie Rose's signature gin, muddled with pineapple juice, orange bitters, maraschino cherry liqueur and crème de cassi (blackcurrant liqueur).

Food is governed by two menus: one for daylight, one for darkness.The daylight offering (think cafe favourites of poached eggs and bircher muesli) ends at 2.30pm. The darkness menu reflects the cafe's mixed-up aesthetic - arancini balls sit alongside dumplings, pulled pork sliders and spicy chicken wings.

Diners around us are happily tucking into a ploughman's board of cheeses, cold cut meats and pickles, but we go for vege sliders, wings and arancini. The servings are well-sized and well-priced. At a bargain $9 a pop, the kickin' wings keep two people happily finger-lickin' through a round of drinks, while the sliders are a humble combination of chickpea patty, hummus and slaw on a crispy milk bun.

The porcini and spinach arancini are more cheese than ball for our liking, particularly when dusted with an added layer of parmesan, but this is a minor quibble. By 9pm, the transition is complete. The after-dinner crowd has rolled in, the music cranks up, and we settle into another round of cocktails.

THE PICKS

Kickin' wings; vege sliders

THE LOOK

Retro wine bar

THE SERVICE

Upbeat and cheery

THE COFFEE

Signature blend roasted by Coffee Masters

THE VALUE

Good. Most bar snacks under $15; cocktails, $18; gin and tonics, $13