“Magic of Christmas” has two acts with one intermission, but it might be helpful to think of the annual holiday concert of the Portland Symphony Orchestra as a collection of thirds.

The first third of the concert is about Christmas traditions. The second third is all about the Christmas story. And the final third captures the spirit of Christmas.

The run of 11 concerts begins with a preview Friday at Merrill Auditorium, and continues through Dec. 19.

Music director Robert Moody has assembled a show similar to last year’s, which was his first as “Magic” director. Overall, this is the 31st year the PSO has presented “Magic.”

Moody will lead the orchestra through seasonal favorites, holiday hits and classical, inspirational numbers.

Joe Cassidy, a Broadway singer who appeared in “Magic” last year, is back. He will reprise his portrayal of Scrooge and all other voices in an abridged retelling of “A Christmas Carol.” Cassidy will also sing Irving Berlin’s classic, “White Christmas.”

Suzanne Nance, host of MPBN’s “Morning Classical” program and a world-class soprano, will join Cassidy and Moody for a “newly discovered” vocal trio from “The Nutcracker.” Moody wrote holiday-themed lyrics for a comedy piece, infusing the classic with good humor and levity.

But the real treat here is the chance to hear Moody sing. Classically trained, he sings like an angel but rarely gets the chance to demonstrate his vocal talents in front of his hometown fans. He gets that chance with “Magic.”

The show opens with a Sousa-inspired setting of “Jingle Bells,” followed by Cassidy’s version of “White Christmas.” Camille Saucier directs the Saco Bay Children’s Choir, which will sing “Somewhere in My Memory” from the movie “Home Alone.” The Saco Bay choir is new this year.

That segment will be followed by the 24-minute narrative of “A Christmas Carol,” with Cassidy telling the tale with orchestra accompaniment. Last year, the PSO commissioned Freeport-based Figures of Speech theater to create three giant puppets to help illustrate the story. This year, Figures of Speech has added two more: Mr. and Mrs. Fezziwig. As a result, the Fezziwig dance will be expanded considerably from last year, Moody said.

The show’s second segment is dedicated to the Christmas story. “The story of the nativity takes on a really great new burst of energy this year,” Moody said.

This section, right after intermission, flows from “O, Come All Ye Faithful’ to Britten’s “This Little Babe” and “O, Holy Night.” The section closes with “Angels We Have Heard on High,” but with the text from “Angels from the Realms of Glory.”

“I saw this done on DVD with Renee Fleming and the Mormon Tabernacle Choir, and have wanted to do it ever since,” said Moody. “This section this year also really needed a tremendous soprano. Suzanne will sing ‘O, Holy Night’ and ‘Angels from the Realm of Glory,’ along with the choruses and orchestra.”

The spirit of Christmas is neatly tucked into the ending. The orchestra’s playful “Sleigh Ride” begins this section, followed by Moody’s lyrical new twist on “The Nutcracker.” Cassidy, who also plays guitar, will perform John Denver’s “A Baby Just Like You.”

Dancing Santas make an energetic appearance, topped by “Let There Be Peace on Earth” and “We Wish You a Merry Christmas.”

At first, Nance considered turning down the chance to join the “Magic” cast. She has been awfully busy lately, and the prospect of 11 performances over two weekends seemed daunting.

But she was overcome by the spirit of the program.

“I thought about Robert Moody, and I thought about all of those singers and that great chorus that comes together, and I thought, ‘This is an opportunity to make festive holiday music with a great symphony and great people.’ “

Staff Writer Bob Keyes can be contacted at 791-6457 or at:

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