While I have not myself invested in film rights, etc., in many years, Section 181 is legit. The question becomes are you the primary investor? Purchasing a partnership interest as a limited partner in perhaps something like a Silver Screen Partnership, LLC? A different type of investor? There is generally no additional audit risk as long as the proper reporting is done and the proper disclosures are made to the partners, shareholders, IRS, etc.
I have given you links to 2 items that may be of interest to you, including the actual code section via the Bloomberg Tax site
Film Production Costs
Section 181
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