Diane Warren: Relentless is a groundbreaking documentary that reveals the unique genius of a woman who has shaped an entire generation of music. Having written over 400 songs for iconic artists such as Cher, Beyoncé, Taylor Swift, Celine Dione, Lady Gaga, Whitney Houston, Britney Spears, and Aerosmith, Diane Warren resides in the pantheon of music greats. This is her untold story.