A tantalising glimpse of buried treasure in Jamaica! Let's take a closer look. To follow along, click this link: https://collections.ushmm.org/search/catalog/irn604656

Click ‘Search this collection’ and enter ‘Jamaica’ (or ‘Morgenthau Jamaica’).

Here is the finding aid for the whole collection:
https://collections.ushmm.org/findingaids/2015.255.1_01_fnd_en.pdf

Here are the most relevant files:

Morgenthau Family Papers, US Holocaust Memorial Museum, Series 1: Family papers 1860-2006, File 145: Television Projects Set in Jamaica 1955-1956, 2 folders [Note: has perhaps only the first folder been made visible in error? There is no obvious divide in the digital scans.]

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• ‘Captain Jamaica of the CIC’ proposal, 9 April 1956: jpegs 157-174
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• Letter from Morgenthau to Fleming, 16 July 1956: jpegs 133-136 (copied elsewhere in this folder: 114-117 and 118-121)
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• Letter from Fleming to Morgenthau, 19 July 1956, including his ‘Commander X’ title suggestion: jpegs 127-130
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• Undated proposal for TV film production in Jamaica, including an adventure show primarily aimed at children titled ‘Adventure Harbor’ and an untitled show and possibly feature film set in a hotel resort with Noel Coward as MC (it seems likely this was sent to Fleming, hence his mention in his 19 July letter of Coward being unlikely to be interested): jpegs 154-156
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• Undated ‘Commander Jamaica’ proposal (possibly also sent to Fleming): jpegs 144-149
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• Letter from Fleming to Morgenthau, 27 August 1956, saying he has airmailed ‘a 9-page outline of the whole series and a 28-page script for the Pilot’ for ‘James Gunn - Secret Agent’: jpeg 140
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• Jo Stewart, Curtis Brown, to Morgenthau, 29 August 1956: jpeg 138
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• Jo Stewart, Curtis Brown, to Morgenthau sending the outline and pilot script, 4 September 1956: jpeg 143
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• Jo Stewart, Curtis Brown, to Morgenthau, 1 October 1956: jpeg 137
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• Letter from Morgenthau to Howard L Hausman, William Morris, 10 October 1956: jpegs 123-124
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• Howard L Hausman, William Morris, to Morgenthau, 15 October 1956: jpeg 131 (and also 126, but unsigned)
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• Letter from Morgenthau to Fleming, 3 December 1956: jpeg 122
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• Michel Bouche secretary to Howard L Hausman, William Morris, letter saying attaching outline and first episode script to Morgenthau, 30 October 1956 (but no attachment): jpeg 125

Series 9, File 53 contains photographs of Jamaica taken circa 1955, which looks like it could be part of the research and scouting for the series.