When Jane Fonda granted us an interview to talk about her famous workout tape, things didn't go as planned.

On part one of a special two-part Decoder Ring, we explore the decades-long friendship of Jane Fonda and Leni Cazden, the relationship that birthed the workout that changed the world. It's a story of creation, regret, fame, forgiveness, trauma, survival, politics, and exercise. In two weeks, we return with part two: the story of the bestselling VHS tape of all time.

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