She was twice his age, her vermilion hair matched his red velvet suit, and her three-and-a-half-inch sparkly-gold tango shoes allowed her to peer over his head — by at least a foot. Who was he dancing with? His grandmother? His great-aunt?

It was one of those evenings of watching others dance tango, and spending a little too much time on the sidelines, not dancing — having not been asked. Tango etiquette has some antiquated rules of engagement, and the one that causes the most chafing is that men do the asking. If that weren’t problematic enough, combined with the lead-follow imbalance, the New York tango cliques, and the exclusive couples, it can all add up to doing some extra time on the bench.

That night, I had plenty of opportunity to track this truly odd couple as they circled the dance floor for yet another go-round. She had the air of an Upper East Side heiress, meticulously preserved, costumed in something beaded, asymmetrical, and slit halfway up her thigh. He looked like a grinning, dance-hall dandy, with a pencil-thin mustache, and penguin-like, as he sported a pair of black-and-white spectators. If he’d been wearing a hat, he’d have tipped it as they tangoed on by.

I asked the woman sitting next to me about the mismatched pair, who never split up, even though tango protocol states that you change partners after each set. “She hired him,” my bench-mate said. “She what?” I asked. “She hired him for the evening. They’re taxi dancing,” she said.

As it turns out, there’s a foolproof way to make sure that you’re not a tango wallflower. You can buy dancing insurance! It comes in the form of a partner for hire, a taxi dancer. A tango escort service, if you will.

* * *

During the 1920s and 1930s, taxi dancing was a popular ticket-a-dance arrangement that operated in closed dance halls. “Closed” in that female customers were not admitted, which opened the door for a new kind of non-domestic, urban job opportunity for unmarried working-class women. Dancing female employees. Male patrons would present a ticket to a chosen dance-hall hostess, and the pay-as-you-go, ten-cent agreement would last the length of a song. Taxi aptly, though indelicately, refers to renting her — on the meter — not unlike cab fare. This of course was considered a scandalous profession chosen by — you guessed it — morally corrupted women. Today, though, with morality up for grabs and corruption setting its sights on loftier goals, the notion of taxi dancing, once thought of as illicit, now seems quaint. Today, on the tango dance floor, faced with a dearth of good leads, hiring a male dancing escort just seems like a really good idea.

One night at a milonga (tango social) I asked my beloved teacher, Dante, if he felt pressured to dance with his students outside of class. Was he aware that some of his female students tracked him around the dance floor? Making sure they knew where he was, who he was dancing with, and then getting into position so when the music stopped, they’d just happen to be within asking-them-to-dance distance. Kind of, if not exactly like, what I was doing with him at that moment. I told him that I respected his right to have a tango social life, and while I didn’t expect him to dance with me beyond the studio, if he asked, I wouldn’t say no. “Nancy” he said, “There is a way that you can dance with me often, you know.” “How’s that?” I asked. “You can hire me,” he said.

So, reader, I paid him.

Deal struck, and joy to be scheduled, Dante and I made a date to take our tango trade agreement out for a whirl. We met on a warm fall evening at my favorite outdoor milonga, Riverside Gypsy Tango, held at the Soldiers’ and Sailors’ Monument on the Upper West Side. Built atop a promontory, just north of the marble monument, and down a grand staircase is a charming, formal, amphitheatre-like terrace.

* * *

The balustraded balcony, surrounded by curved granite benches, sits high in a crown of trees. It’s a perfect place for contemplation, assignation, and Shakespeare reruns. Decked with 800 pounds of portable parquet flooring, it’s perfect for Argentine tango.

We sat down on one of the stone benches to plot out our evening’s dance card. Milongas are carefully configured tango socials made up of dance sets, or tandas. Each set is composed of three or four songs of the same style of tango, and usually from the same orchestra. To signal the end of the set, a cortina, a 30-second piece of non-tango music, is played. This musical-chairs-like interlude is the time to change partners, pop a breath mint, go to the bar, or rest your dancing feet.

Dante suggested that spacing out our hour’s worth of tandas was a good strategy as it gave us each the chance to dance with others, and maybe avoid the appearance of a financial arrangement. But paying to play didn’t bother me — much. I was ready for a night of marvelous dancing in the arms of a smart, handsome, funny, sexy tanguero, who was a beautiful dancer and knew how to show a tanguera a good time.

The Argentine tango is a deceptive dance. From the outside, it can look like an intimate conversation that, once started, is best finished off the dance floor. Deeply woven in each other’s arms, lips brushed up against a cheek, and with its leg-entwining antics, you’d think the tango was all sex. What makes it so intoxicating, though, is that the tango is really an inside job — a hypnotic, dancing meditation. The goal, and then the pleasure, is to dance as one, to tango’s time-honored steps, to be so merged that the separate self is abandoned. Well . . . kind of like sex.