You step into a dimly lit lounge and casually shake off the fog’s chill.

A bar glows gold to your right.

A live Coltrane number hits you from a stage somewhere over in the corner.

And is that a patty melt you smell?

You haven’t time-warped yourself into a Dashiell Hammett book. You’re at Mr. Tipple’s Recording Studio, a come-hither new lounge with jazz, draft cocktails and future-you with a lovely date wrapped around your arm. It opens Tuesday in Hayes Valley, here’s the slideshow, and here’s the menu.

It’s got art deco touches. It’s got live jazz every night. It’s got drinks from a Nopa/Maven/Brass Tacks vet. It’s got food that pairs well with those drinks. And perhaps most importantly, it’s got a semiprivate, curtained-off space called the Opium Den.

But we’ll get back to that.

First, claim two seats at that glowing bar and order a round of Equators. Two daiquiri-like rum drinks made with coffee-laced honey and hellfire bitters will appear. Or, alternatively, one of the off-menu cocktails on tap that you knew to ask for. Drink those. Listen to some jazz. Smile at each other.

And when it’s time, raise an eyebrow. The eyebrow that says, “Opium Den?”

Not the one that says, “Patty melt?”