Proof of Life (2000)
Proof of Life is a 2000 American film directed by Taylor Hackford. The title refers to a phrase commonly used to indicate proof that a kidnap victim is still alive. The film's screenplay was written by Tony Gilroy, who also was a co-executive producer, and was inspired by William Prochnau's Vanity Fair magazine article "Adventures in the Ransom Trade," and Thomas Hargrove's book The Long March To Freedom in which Hargrove recounts how his release was negotiated by Thomas Clayton, played by Russell Crowe, who went on to be the founder of kidnap-for-ransom consultancy Clayton Consultants, Inc.
More at Wikipedia.