Derek Cianfrance - Eva Mendes Had The Chance To Select Her Mum For New Film

The Training Day beauty admits she had to go to a dark place for the role of a single mother, who is faced with a difficult decision when her son's birth father suddenly shows up at her doorstep, and the director suggested she invite her mum to the set to help her cope with the drama.

She says, "One of the beautiful things that Derek did was he told me to cast my mother... He did ask me if my mother (would be interested). I said, 'My mother is amazing, but I don't think she would wanna play in this film because it's a little dark for her.' But he did try to get me to cast my own mother."

The actress turned casting director to select her onscreen parent, Olga Merediz, and Mendes admits the hands-on process made all the difference in their mother-daughter chemistry.

She explains, "He (Cianfrance) said, 'You're going to New York tomorrow and you're going to cast your mum.' And I said... 'Oh, you want me to meet people, let you know (who I like)...' He said, 'No, I want you to cast your mum, whoever you meet that day... that you feel is your mother, that's who's gonna have the role.' And I said, 'That's beautiful and amazing and unheard of.'

"I thought for sure he was gonna go back on it; I read with about 20 women and I met Olga and I was like, 'Mummy!' She was so amazing. She reminded me of my own mother and then when I told Derek, he was like, 'Great, we got her!' And I was like, 'Don't you wanna see something?' He's like, 'Do you feel like she's your mum?' and I'm like, 'Yeah I do,' and he said, 'That's all we need.' There's no other director doing that."