It shook the world. But why do some suspect darker forces were at play?

Stream 9/11 - Truth, Lies and Conspiracies on BBC Select

Half of Americans believe they haven’t been told the whole story about 9/11. We’ve all heard the conspiracy theories, but why do they continue to grip some people so tightly?

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9/11: Truth, Lies and Conspiracies on BBC Select

In this thought-provoking exploration of one of America’s greatest tragedies, victims’ families, a senior politician and intelligence agency insiders discuss their belief that there’s much more to this story than we know.

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