There are plenty of reasons why "The Fantasticks" is the longest running musical in history, with more than 17,000 consecutive performances in New York.

But once you get past all the funny stuff and the wonderful songs and the strong characters like El Gallo, you are left with the single thing that has made this such an overwhelmingly popular show. 

The simple little musical is about a boy and a girl and being in love.

The latest iteration of this musical was unveiled at Off the Wall Theatre Thursday night, and the uneven production did no favors for the millions of people who have loved this show ever since it hit the stage over 50 years ago.

The thing you need in this show is chemistry between Matt and Luisa, the boy and the girl. There needs to be spark, juvenile heat, the kind of thing that makes adults smile knowingly.

And in this production, it just wasn’t there.

Maura Atwood, who has a lovely mezzo, plays the girl; Daniel Slattery plays the boy. They could not have been in further apart and in more different worlds.

Atwood is a good singer with a wispy manner that gave her all that a 16-year-old girl in love should have. She was the embodiment of that teenager even if she at times saw the timber in her voice slide into an almost falsetto. But she was clear and concise in who she was supposed to be on the stage. 

Slattery was badly overmatched. His voice was thin and without the kind of emotional heft needed for songs like "Soon It’s Gonna Rain" and the duet with Luisa, "They Were You." Slattery is a bland blonde who doesn't look or move at all like a boy for whom love is just one of the horizons he wants to reach. He has little of the kind of romantic attraction that you would normally expect in a boy in love with a teenage girl.

It was almost as if he learned the words to the songs but didn’t bother trying to figure out what those words actually meant. The contrast between him and Atwood was striking and painful.

The contrast with El Gallo, the mysterious narrator created by Jeremy C. Welter, was even more stark. 

Welter commands a stage, whatever the role. He brought a kind of world-weary sinisterness (I hope that's a real word) to this El Gallo, menacing at one moment and painfully needy at others. He is not a great singer, but Slattery could learn a lot from seeing Welter work a stage and provide weight to the lyrics of a song. He isn’t going to win the television show "The Voice" this season, but you never doubt that he understands and feels what he is singing.

"The Fantasticks" is full of good humor, much of it provided by Marilyn White and Carole Herbstreit-Kalinyen as the two fathers. They are a couple of Milwaukee stage veterans and delivered just the right amount of humor – without falling prey to the temptation to overact that others gave in to, falling flat time after time.

I have seen this play over 100 times in my life, courtesy of free tickets while I was in the Navy, and have loved it since the first time I saw it. It is such a popular play that it is performed at all levels, from professional to community to high school theater groups, each year. It’s an easy play to mount, with a simple set and simple costumes and simple music.

There are those who say this play is past its expiration date, but I don’t buy it. Sure, there are things that seem anachronistic and impolitic, like a song about what kind of rape should be staged for the production.

But the story of a boy and girl in love is a story that doesn’t die of old age. In this case, the death was really the fault of one of those two being unable to hold up his end of the deal.

 "The Fantasticks" runs through April 30 and information on tickets and showtimes is available here.