The theater was jammed with Pink Ladies and Burger Palace Boy wannabees before the curtain even went up on Hackmatack's version of "Grease." It just goes to show that some shows will never go out of style.

Traditionally, Grease is cast with actors old enough to be the parents of the characters they portray (Stockard Channing was 35 when she portrayed the character of "Rizzo" in the movie; John Travolta was pushing 30). Steven Huff decided to go the other way and cast actual high school and college students; the result is an energetic, fresh, exciting good time.

Everyone knows the story: a straight-laced girl has a summer romance with a boy from the wrong side of the tracks, only to find the romance gone awry when brought back to the pressure-cooker of their high school. They spend the rest of the school year trying to wrestle their romance into their circle of friends, as they go about the business of growing up and realizing that being yourself, but also exploring new avenues, is the best way to make friends and fall in love.

As Danny Zuko, Brandon Heath is sarcastic, witty and- when he's around Sandy-completely tongue-tied. Sandy (Heidi Gagne) is bookish and shy, but emboldened enough to stand up for herself when she realizes Danny is treating her like just some ordinary girl instead of the love of his young life. Conor Guptill as Kenicke uses his comedic flair to endear himself to the audience, while Morgan Mosher as Marty, whose tiny frame belies her huge voice, blows us away with her talent. Brett M. Wufson is adorable and funny as Frenchy. Dremessa DiNardio as Rizzo brings a delightful mix of toughness and vulnerability to her role. Chris Gallot, as both Vince Fontaine and the Teen Angel, gives us a beautiful voice and facial expressions full of sarcasm and smarm. The rest of the ensemble fills out the cast with the same kind of youthful zest.

The set design by DeWitt Hardy is clever and bright. When the Greased Lightning jalopy (designed by Chris Gallot) pops out of the center stage door, it's humorous but appropriate. Jane Forde, choreographer, makes use of the entire stage and set. Her '50s style dances fill the entire barn with energy. Fran Bechtold's costume design, full of fluffy poodle skirts, angora sweaters and leather jackets, sets exactly the right tone for the musical.

"Grease" runs through July 31, Wednesday through Saturday at 8 p.m., with a matinee on Thursday at 2 p.m., at Hackmatack Playhouse, 538 School St. (Route 9) in Berwick. Tickets are $18 adult, $16 senior, and $10 for students (under 20) and children. Saturday night prices are $20 adult, $10 for students and children. Reserve tickets by calling the box office at 207-698-1807.