Is Hollywood legend Rita Moreno New York City’s ultimate cougar at age 91?

We hear the “West Side Story” icon attended Tuesday evening’s performance of the new Broadway sensation “The Sign in Sidney Brustein’s Window.” (She played the female lead in its 1964 original run).

And we’re told that after the show, she got cozy with the new production’s stars — “Star Wars” actor Oscar Isaac and the “Marvelous Mrs. Maisels” star Rachel Brosnahan — over champagne in the lobby of the James Earl Jones Theatre.

Stage spies say Moreno gushed about the pair’s onstage chemistry, calling it “red hot” and “carnal,” before asking Isaac if he was “single and into older women.”

Then the nonagenarian EGOT-winner told him, we’re told, “I have a thing for brooding actors. I dated Marlon Brando, you know.”

Isaac, who’s married with two children, demurred, “Brando’s a very tough act to follow.”

There’s quite a tale there, too.

Moreno, who met Brando when she was 22 on the set of the 1954 Napoleon biopic “Désirée,” told Variety last year, “He was extraordinary in many, many ways, but he was a bad guy. He was a bad guy when it came to women. I was such a different person then. I had all the makings of a doormat.”

She added, “I could read him like a book and that’s why he loved me, and that’s why he mistreated me in so many ways. I tried to end my life with pills in his house. That’s how I tried to do it.”

Perhaps she should steer clear of brooding actors for her next fling anyway.

The show opened at BAM earlier this year, but got transferred up to Broadway at record-breaking speed.