Leah McSweeney of ‘Real Housewives’ Takes a Cold Plunge

“Oh my God, this is insane,” said Leah McSweeney, the reality TV star. “I might die. You might have to call. …” Her voice cut off as her head slipped below the water. It bobbed back up a second later as Ms. McSweeney fled the frigid plunge pool and reached for a towel. “I was honestly afraid you would have to call an ambulance.”­­­

This was on a recent afternoon at Wall Street Bath, a Russian bathhouse behind scaffolding, in a basement, on the fringes of the financial district in Manhattan. Ms. McSweeney, 39, a star of the latter seasons of “The Real Housewives of New York City,” has been a regular patron for nearly a decade, enjoying the sauna, the shvitz, the treatments. In the 12th season of “RHONY,” she brought her moneyed co-stars to the spa. Ramona Singer called it “rustic.”

But, as Ms. McSweeney told the camera, “This is my oasis for relaxation and detoxing.”

Now that Ms. McSweeney is sober, she has fewer toxins to dispose of, but on this breezy spring afternoon, a few weeks after the publication of her first book, “Chaos Theory: Finding Meaning in the Madness, One Bad Decision at a Time,” she returned to steam, sweat and calm herself down.