My teenage daughter is interested in a Murder Mystery party with her friends. We found several websites that link you to kits. We did one quite a few years ago with my in-laws and kids and had a blast.
There are quite a few themes for teens and kids as well as adults. It is always a good idea to read the reviews and synopsis before picking your mystery kit. If you are really creative you can create your own mystery dinner party but I would suspect that may take more time than most people have!
Here are some links to what we found (but have not tried yet):
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