Book, music, and lyrics by Meredith Willson. Story by Meredith Willson and Frank Lacey. Directed by Barbara Tomasic. A Gateway Theatre production. At the Gateway Theatre on Friday, December 9. Continues until December 31

It’s big, brassy, and a whole lot of fun. This beautifully executed production of The Music Man injects a warm shot of sunshine into our icy December.

The play is set in 1912. Prof. Harold Hill, a notorious con man, blows into River City, Iowa, and convinces the townsfolk that the new pool table in the billiard hall will bring nothing but trouble. His solution? Get the kids to form a band! Never mind that Hill knows nothing about music; he has a revolutionary “think system” that will magically enable his charges to play.

The mayor is skeptical, and he tasks the four members of the local school board with finding out Hill’s credentials, but Hill repeatedly distracts them by directing them to sing in harmony, a tactic that gradually transforms them from feuding bureaucrats into a giddy barbershop quartet. Even Marian Paroo, the prim librarian and music teacher who’s initially impervious to Hill’s charms, begins to soften.

Director Barbara Tomasic and choreographer Suzanne Ouellette skillfully integrate the complex rhythms of Meredith Willson’s songs into the play’s action. In the show’s opener, “Rock Island”, a group of salesmen on a train repeat syncopated phrases while their bodies jiggle with the rocking of the rails. In the sinewy “Marian, the Librarian”, Marian’s checkout stamp becomes part of the percussion. And the big numbers, like “Seventy-Six Trombones” and “Shipoopi”, are a joyous riot of movement.

There’s a lot to praise in this energetic cast of 26, which includes several children. Jay Hindle is a smooth-talking Hill, who fluidly manages the demands of his syllable-stuffed songs. Meghan Gardiner’s Marian is self-assured, but there’s a strand of tender vulnerability woven in there, and her ballads (“Goodnight, My Someone” and “Till There Was You”) showcase her gorgeous voice. Joel Garner as Mayor Shinn and Jennifer Long as his wife, Eulalie, also do strong work, and Chris Lam, as fellow con man Marcellus Washburn, impresses with his singing, dancing, and especially his wicked comic timing.

The visuals are a treat: Marshall McMahen’s set uses handsomely painted backdrops that allow plenty of space for the pastel rainbow of Carmen Alatorre’s costumes. And there aren’t quite 76 trombones in the pit, but Christopher King’s tight 10-piece band fills the house all the same.

Hill’s gift of harmony to River City ultimately proves to be more than a con job; it transforms him as well. A musical with a hopeful message? That’s a perfect gift for the holidays.