Director Juan Antonio Bayona and screenwriter Sergio G. Sanchez would never have made "The Impossible" if it wasn't for their producer's chance discovery of a radio program featuring Maria Belon, a Spanish wife and mother who along with her family survived the 2004 Indian Ocean tsunami.
That initial discovery led to a long-term relationship with Belon, her husband and their three sons.
The collaboration extended from Sanchez's script onto the set of the film. She spent hours with Bayona and Sanchez as they were writing the screenplay. She wrote long, lyrical letters to Naomi Watts, who portrays her in the film. Even composer Fernando Velazquez received a surprise visit from Belon when he was composing the score for the film.
In this excerpt from the Envelope Screening Series, Bayona, Watts and Velazquez discuss their time with Belon and what the woman added to the film. All three found their relationship with her only added to the film's authenticity and in the case of Watts, affected her actual performance.
For more insight into "The Impossible," which opens on Dec. 21, take a look at the video above.