There’s a new secret dining society in town from the folks behind the Hawthorne and Menton. Its name: Brasstacks. We took it upon ourselves to infiltrate a recent dinner and file this report. Fair warning: the dinner was last night, so our mind is still a little foggy.

You’ll start on Facebook.
Friend them. Demand a seat at their next dinner. (Or just ask nicely.) Wait for the date and secret location to be sent to you.

Prepare for a Dead Poets Society vibe.
Last night’s space: a modern two-story South End brownstone overlooking the park. The lighting: by candle. The decor: heavy on piano parts and large surveyor sticks.

And not many people.
Last night’s dinner had 11 people. This included a Harvard physicist, a French financial analyst, a pastry chef and a Web advertiser.

Show up hungry. And wine-thirsty.
On the menu: lamb charcuterie. Then six courses of an entire lamb, taken from a secluded island off the coast of Maine. Also: cod’s throat. All of which was paired with wine.

Don’t make other plans.
Last night’s event took four and a half hours.

There’s more where this came from.
The organizers plan to open a restaurant in eight to 10 months. And later, a fondue-serving dive bar. Because nothing says secret dining society like cheap beer.