A funny thing happened at Dead Letter No. 9, a new performance space in Brooklyn. It was just after 10 p.m. on a Saturday in late October. The evening’s show had finished, but the audience wouldn’t leave — crowding instead into the adjoining bar for cocktails, mocktails and flatbreads.

Though New York City has its cabaret spaces and piano bars, theater and nightlife mostly occupy separate addresses. Blame temperament or real estate or the lingering effects of cabaret laws (finally repealed in 2017), which required a license to allow patrons to dance, but in general those who long for a drink and a show at the same time have had to settle for overpriced chardonnay in sippy cups. Ah, the glamour.

New shows and new venues are blurring those lines. Though I am a lady with a hilariously low tolerance for alcohol who likes to be in bed just as the cable TV shows are getting good, I attended three of these performances over the last few weeks, trading a good night’s sleep for this superabundant approach (drinks, snacks, dance, card tricks, elaborate lingerie) to evening entertainment.

I began with “Dead Letter No. 9,” the name of both the show and the nondescript building that houses it on Grand Street in Williamsburg, not far from the East River. After entering through the wrong door, a friend and I were redirected to a different one, which led to the space’s pleasant, unassuming bar. A seltzer later, it was time for the show to begin.

The front of the space proper was a dimly lit mail room, stuffed with mislaid letters and lost packages. We were outfitted with Casio watches and handed a letter of our own, an invitation to a 2007 graduation party in Redding, Conn., then led down a hallway and into a small room decorated like a treehouse. (There were two other rooms available: a North Carolina porch from 1986 and a California camp from 1993.) We took a seat on a creaking metal cot. Four other audience members reclined elsewhere. A host dressed as a mail carrier offered us vodka, beer and bottles of Mike’s Hard Lemonade.

At first the conversation was of the stilted where-are-you-from and how-did-you-find-out-about-the-show variety. Then, as minutes flashed by on the Casios and other participants mixed vodka into their hard lemonade, everyone relaxed. People went. People came. When the mail carrier left, the father of the ostensible graduates joined us. He seemed to want to talk about an old soccer injury, but the rest of us had come to know one another by then. We had our own story lines to pursue. I somehow found myself talking about both Frankfurt School critical theory and the time a magician sawed me in half. (Yes, I was sober. And no, I don’t get out much.) After a very quick hour, the Casio alarm beeped, a signal that we had to leave the room. I never did learn much about the graduating kids.

When my friend and I exited, the people who had left before us were waiting in the bar area. As a piece of theater, “No. 9” was thin, stronger on atmosphere than on narrative or action. But as an icebreaker, it was maximally effective. Everyone seemed to want to stay and keep the conversation going. A few cast members, who had since changed out of their costumes, joined, too. Attendees could then head deeper into the space, where a dance floor waited.

“If I want to go wild in a nightclub space, I’d love to be able to do that in the same room that I could have a quiet bite and a rich conversation,” Michael Ryterband, a creator and the sound designer of “No. 9,” said in a recent interview. “That’s what we made. This is absolutely a nightlife alternative.”

His business partner Taylor Myers, who directed the production, gently corrected him: “It’s not an alternative. It is nightlife.”

The next week, I took the L train a few stops farther into Brooklyn to “Cocktail Magique,” a show from Company XIV that began performances about a year ago. I had found the company’s previous shows, like “Seven Sins,” effortfully sexy, even exhausting. But “Cocktail Magique” is a looser, giddier affair, beginning with an upscale Jell-O shot (chartreuse!) and ending with a frozen dessert in the shape of a chicken leg, with a lewd balloon animal routine in between.

“I really like the space to feel like it’s as much a party as possible, really feel abundant and inclusive,” Austin McCormick, the company’s founder, told me.

“Cocktail Magique,” created and directed by McCormick, takes the form of a playful burlesque revue. New York is not lacking for burlesque, but unlike the Slipper Room or House of Yes, in which the acts function as addenda to the bar service, “Cocktail Magique” is the purpose-built space’s sultry, boozy raison d’être.

Audience members sit facing the stage, decorated in a riot of jungle animals and filigree. Strong cocktails complement the various burlesque routines, which include a dance number set to “Love Potion No. 9” and a balancing act atop champagne bottles. The magic may not dazzle, and not every scene is exactly tasteful (there’s a homage to Josephine Baker’s banana dance), but the performers, gorgeously appareled, are superb and their delight is intoxicating. (So are the powerful cocktails, which I had to abandon after a trial sip.) The emphasis was on beauty and excess, from the iris-infused gin in the Cleopatra’s Pearl to the custom corsetry and glitter pasties adorning the male and female performers.

As at “No. 9,” the crowd lingered, finishing their cocktails and chatting about what they had seen. McCormick, who also operates another space nearby, dreams of a theater that could transform into a nightspot.

“People love to hang out and have a drink and mix and mingle,” he said. “My fantasy is a place where we can do something cool after the show.”

Grimmer fantasies were on display at “Hypnotique” at the McKittrick Hotel, which also hosts the soon-to-close “Sleep No More.” The McKittrick, in Manhattan, has often sought to extend the evening with magic shows, concerts, parties and other events. Billed as a night of “spontaneous performances and mesmerizing dancers,” “Hypnotique” is a strip show and one of the most joyless displays of eroticism I have ever seen — a dutiful, glitter-addled march from one display of bare breasts to the next. Spontaneity had fled.

Created by Whitney Sprayberry and Reginald Robson, “Hypnotique” invites audiences — their phones locked away — into the Club Car bar where four men in mesh shirts made sexy faces and moved furniture as a chanteuse sang “Light My Fire.” They were soon joined by six women in printed robes, sunglass and granny scarves. The scarves come off. So does nearly everything else. Set to songs like “Need You Tonight,” “Lucy in the Sky With Diamonds” and “Bad Girls,” the routines were beautifully executed and almost entirely soulless. I have felt more frisson at P.T.A. meetings. My fire? Unlit.

The parade had an unvarying quality, with no routine complete until a dancer had freed her nipples. The dancers were slim, beautiful and — in contrast to the gleeful, polymorphous perversity of “Cocktail Magique” — mechanical and unenthusiastic as they wriggled and unhooked. (I believe in the right of any woman to take off her clothing. I just want her to look as if it’s her idea.)

I did, however, enjoy the strobe-lit feathers that flew during a pillow fight scene and the yassified leaf blower used to tidy them. After the final balconette bra had been removed, the evening likely evolved (devolved?) into a dance party. I wouldn’t know. It was past midnight, past my bedtime, and past several decades of feminist thought and gains. I was already poured into the back seat of a car, zipping toward Brooklyn where a book and a mug of herbal tea — my nightlife alternative — were waiting.