“Little Shop of Horrors,” maybe my all-time favorite musical, is returning to New York City. Here are some things to know: *Ellen Greene’s performance in the original off-Broadway version is storied, to say the least. She was so excellent, she returned for the movie (though the directors surely could have opted for a bigger star). Ellen Greene is so outstanding, she returned for a recent Jake Gyllenhaal revival, though she was (and is) much older than Jake Gyllenhaal. And people went wild. (I feel bad for anyone asked to play Audrey who is not Ellen Greene. ) *Jonathan Groff, the star of the new production, has an odd history. He has bounced from “Frozen” to “Hamilton” to “Mindhunter” to “Looking.” That is just a strange career. Mr. Groff has renounced social media; he doesn’t believe he is interesting enough. A favorite activity of his is to return to his rural Pennsylvania hometown to see high-school productions of musicals. (I love this.) Mr. Groff is not the most exciting perfo...