Let us all agree, before we even begin, about what Junie B. Jones is not.

She is not a crook. She is not a nutball (at least not totally). She is not in love with Handsome Warren, even though she likes him a lot.

What she is, though, is the center of a wonderfully funny story, "Junie B. Jones Is Not a Crook," the play based on the famous children’s book that opened over the weekend at First Stage.

The outing is the first directorial chance for James Fletcher, who has been involved with the company for 17 years as actor, fight choreographer and teacher. It is an auspicious debut thanks to a great cast of adults and kids – and one actor who delivers the kind of performance that makes you shake your head in wonder.

Her name is Molly Domski. She’s a 10-year-old fourth grader, and she plays Junie.

First of all, it’s a huge part, on stage almost throughout the entire show and the center of attention every moment. But you can teach lots of kids to memorize so many lines and to follow directions.

What you can’t teach is the little things. The quick roll of an eye, the disciplined drop of her head into a slumber in class, each movement timed to the tick of an unseen clock. The look of exasperation that creases her little face as she tries to fathom what it is that makes her friend Lucille (Grace Fischer) tick. The grace with which she shows off her soft mittens that play such a huge part in this story.

Molly is an absolute pearl of an actor. She has a physical, emotional and intellectual depth that is stunningly surprising in one so young.

She was not alone in building this show into one of the most delightful mounted by First Stage in several years. Kay Allmand, Dan Katula and Lachrisa Grandberry all play the various adult roles with the kind of professional panache you always get at First Stage. Allmand is a delight playing two characters as different as night and day.

But it’s the kids, the Found Cast in the show I saw, who carry this show.

Junie has two best friends, Lucille and Grace (Faith Austin). Grace is a young athlete and Lucille is a prissy American Girl doll who delights in telling everyone the cost of her dress, her shoes, her hair – minus the sales tax.

The three girls are joined by four others: three boys, John Aebly, Gave Lorenzana and Carson Pressley, and a fourth girl, the always delightful Lina Singh.

The story is about theft of mittens, magic pens and boyfriends, and Junie is both a victim and a suspect, spending a lot of time trying to prove that she is really neither.

Junie is not, however, without her difficult personality traits. She’s a talker, everywhere, including school. She is honest, to a fault sometimes. She is hungry to be accepted as a girlfriend, a friend, a … whatever.

But there is a lesson to be learned from Junie and Allmand as her mom.

Junie wants a trip to the mall for a dress, for jewels, for things that will make Handsome Warren notice her and like her.

But her mom points out, with the kind of resolute certainty that seems to only belong to mothers, that Junie won’t make friends with "things." She will become a friend by being nice to people, caring about them, helping them.

It’s a lesson learned quickly by Junie who finds a sorrow-filled Warren, alone on a playground, and only breaks through his sad fence after a series of knock-knock jokes. It is then that Junie, and the rest of us, all realize that the truth of the matter is that friendship, real friendship, comes along only when you can prove how much you unconditionally care.

Working with child actors is always a challenge, but Fletcher has used his years of experience at First Stage and his role as a relatively new father to lead this cast to a place where everybody can have lots of fun.

"Junie B. Jones is Not a Crook" runs through June 4 and information on showtimes and tickets is available here.