Henry Roan has been shot through the back of his head. The local authorities have found his body slumped over the steering wheel of his car. There's no gun at the scene: this is no suicide - it's brutal murder. And the man who ordered Henry Roan's killing? He claims to be his best friend...

Former Principal Chief of the Osage Nation Jim Roan Gray joins Tim Harford to speak about his great-grandfather Henry Roan. They also discuss the Osage Nation today and Jim's take on the new film Killers of the Flower Moon, directed by Martin Scorsese.

This episode of Cautionary Tales was produced in association with Apple Original Films. Killers of the Flower Moon stars William Belleau as Henry Roan, Robert DeNiro, Leonardo DiCaprio and Lily Gladstone.

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