When Howard Shore composed his score to “The Lord of the Rings: The Return of the King” in 2003, he was faced with a massive dramatic responsibility. Not only did he need to provide a fitting conclusion to one of the most fully realized fantasies ever put to paper — or to celluloid, for that matter — but he also needed to draw his own sprawling collection of leitmotifs to a poignant finale.

(The Chicago Symphony Orchestra will perform the score of “The Return of the King” while the complete film is projected on screens in the pavilion and on the lawn for two concerts Aug. 7-8 at Ravinia. Reserved seats are sold out for both nights but lawn tickets remain for Aug. 7.)

“The Return of the King” gathered one of the most extensive thematic catalogs ever assembled for a film score and set it charging relentlessly toward its denouement. If “The Fellowship of the Ring” was about departures, and “The Two Towers” was about perilous journeys, then the final installment was about destinations. Each theme and motif that Shore had associated with the precepts of Tolkien’s work needed to reach a proper conclusion — some triumphant, some tragic.

In short, Shore was presented with same challenges faced by J.R.R. Tolkien and filmmakers Peter Jackson, Fran Walsh and Philippa Boyens. The composer’s fantastic musical landscape needed to both broaden its scope and narrow its focus for the climactic chapter of “The Lord of the Rings.”

Doug Adams’ detailed analysis of the musical themes used in “The Return of the King” can be found in the complete article in Ravinia magazine or at Ravinia.org.