The actor has joined the cast of Warner Bros' upcoming heist movie which will be directed by Glen Ficarra and John Requa, according to The Hollywood Reporter.
The thriller centres on a master conman (Smith) who falls in love with his young protegee - to be played by Australian actress Margot Robbie.
However, he is thrown off his game when his former flame reappears just as he prepares to stage an elaborate heist in Buenos Aires.
Santoro will play the enigmatic billionaire owner of a racing team who is smitten with Robbie's character and hires Smith to give his team a competitive edge.
Santoro recently finished filming 'Jane Got a Gun', a Western film starring Natalie Portman and Joel Edgerton, and will next lend his voice to animated caper, 'Rio 2'.