Harvey Fierstein. Cyndi Lauper. “Kinky Boots.” He’s doing the book. She’s writing the songs. It’s producer Daryl Roth’s musical of Britain’s 2005 film about a broke shoemaker and his drag queen partner. The opening’s April 4. Al Hirschfeld Theatre.

So my phone rings. I’m told it’s Harvey Fierstein. Like with his woolly voice I’d maybe mistake him for Jeremy Irons.

“I can’t remember how many shows I have on now — ‘Newsies,’ ‘Hairspray,’ ‘Torch Song Trilogy,’ ‘La Cage,’ ‘A Catered Affair’ . . . and I just started an idea I had 25 years ago, about a book of photographs.

“Collaborating with Cyndi is great. But harder logistically because I have to work on my own. She doesn’t sit still. Concerts, benefits, always on the road, so if I need two more songs it’s playing catch-up.

“Like I had to stop one number she wrote mid-scene, then reprise it. She said, ‘What’re you doing to my song?’ I said, ‘Musicals need love stories that flow. It can’t stop in the middle. How a song’s used or danced to must serve the story.’ She said, ‘You wouldn’t do this to Rodgers & Hammerstein.’ So I rented DVDs to prove their effort was collaborative. And that recording a demo differs from a song live onstage.

“If a set takes longer to change, my job’s to write around it. You have to write the rhythm of a show. If a song lands, it’s because the book writer is good.

“I never stop rewriting. The movie was a drama. This is a full-out musical. I changed the story. Made it into one about a failure who didn’t want the business and a boxer who becomes a transsexual. Musicals have to have two people.

“Now Cyndi’s hanging out at rehearsal. She’s loving the process.”

So, about all this money you’re making . . .

“Please. Five years ago I tore down my Connecticut house, which was a barn and is now one huge room. What I’m doing with my money is paying off the mortgage.”

RACHEL Weisz: “Shoes are an actor’s foundation. Most important part of a character. Your walk can turn you into a different person.” Also: “Blondes are guy magnets. Men are conditioned, or it’s genetic. A nature/nurture reflex thing. When I played a blonde, men reacted differently. Turned their heads in a way they didn’t normally.” Meanwhile, Rachel’s natural brunette hair nailed husband Daniel Craig.

CARE to catch Katharine McPhee and Debra Messing in person? Between scenes shooting “Smash,” they dodge traffic to run across from the Lyceum to Bond 45 for antipasto breaks . . . Oscar nominee for “The Master” Joaquin Phoenix told the London Times: “I still think of myself as 18. I can’t quite handle actually aging. I think a lot of actors are adult children.”

WHAT kind of tiger growled in “Life of Pi”? Computer job, based on their actual moves, took a year to re-create with 10 million hairs stuck onto each. Booked were 20 real ones. Maybe there’d have been more, but the others had no agents . . . Billy Crystal told the Hollywood Reporter he hosted nine Academy Awards “and never watched even one of the tapes.”. . . Derek Jeter gets a fortune to promote Ford. However, he drives a Mercedes.

AT restaurant Da Tommaso: Obama’s acting more presidential daily. Especially when you consider his trips to the Middle East. Unfortunately, he was heading for Canada at the time.

LOOMING is a real estate kerfuffle. The UN wants expansion on the United Nations’ north lawn. The state, city and neighborhood suggest more suitable is Robert Moses Playground on downtown’s south side.

Immediately north of the UN, 48th and 49th’s east side of First Avenue, the United Nations Plaza’s twin 860/870 towers house 1,000 residents. Besides diminishing their natural light, increased vehicular density at the FDR entrance ramp, loss of river and skyline views and a green park land, which is a global historic landmark, their drop in value would be dramatic. Construction would also eliminate proceeding with NYC’s Greenway project around Manhattan.

Fifty designs are currently being evaluated.

State Sen. Liz Krueger: “We’re in bad economic times. There is no funding for improvements to a park space or new esplanade. It will not help New York City make good on its commitment to a green ring around Manhattan. I see no money on the horizon for another large building on the north lawn.”

OVER the spaghetti bolognese aroma at Nello, what’s a movie star discuss? The potty. Matt Damon, with the missus Luciana and designer Naeem Khan, burbled to Hampton Sheet’s Joan Jedell about his new viral video that calls for a toilet strike: “It’s a serious subject. 2.5 billion people don’t have access to a toilet and . . . until they do . . . I’m just not going to the bathroom.”

Brings up that old rhyme — hasten Jason, bring the basin . . . whoops, stop . . . bring the mop.

Only in New York, kids, only in New York.