Interesting that Shatner used the Goldsmith music for Star Trek 5. This despite it being used on TNG.
I think the Courage theme is like the James Bond theme of Star Trek.
Although Goldsmith made the signature klingon theme.
That opening scene in TMP when the cruiser appears at the start--that was pretty cool.
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Each theme is excellent in its respective context.
Alexander Courage's theme was perfect for the 1960s television series, especially with its big band swing and lilt similar to I Love Lucy (both shows were produced by Desilu; I wonder if the similarities were deliberate).
Jerry Goldsmith's theme was perfect for the grand, big-budget debut of Star Trek on the big screen.
The TV series theme just wouldn't work for a grand, theatrical space opera, especially in the age of Star Wars. Why else would Gene Roddenberry and Robert Wise select Goldsmith to do the score rather than Courage, other than the fact that Roddenberry originally wanted Goldsmith to score the original 1960s television series, which also explains why Roddenberry reused Goldsmith's Motion Picture theme for Star Trek: The Next Generation? The same goes for why Harve Bennet, Nicholas Meyer, Leonard Nimoy, and William Shatner selected Goldsmith and others to score the other original Star Trek movies.
Before The Next Generation premiered, I had a feeling that the Motion Picture score would be used as the main theme, because Goldsmith's theme, while majestic and formidable, was also generic enough to use in several different contexts of Star Trek, like John Williams' main theme for Star Wars. A close second would be Leonard Rosenman's score for Star Trek IV: The Voyage Home, which was also generic while full of pomp. The scores for II, III, and VI were far more specific to the themes of those movies and not as generic and would not have worked as main themes for separate Star Trek movies and television series.
Further proof that Alexander Courage's original series theme was not suitable for the big screen: Michael Giacchino's corny and campy treatment of it in the end credits for the J.J. Abrams/Bad Robot so-called "Star Trek" films.
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