The filmmaker had been struggling to find an appropriate musician to take on the small role until De Niro offered to reach out to his Righteous Kill co-star and invite him to the set.
Actor Romany Malco, who appears in Last Vegas with De Niro, Michael Douglas and Morgan Freeman, says, "There was this one instance where we needed a gangster rapper to be in this one scene. We're getting closer and closer to the day we needed to shoot and we needed to find one and the director was panicking, and De Niro steps up and goes, 'Who do you need...? You want 50?'
"He literally pulled out his phone, and speed dials: '50, you wanna be in my movie?' All I heard was, 'Yeah'. Next thing you know, jets, bodyguards (turn up onset)...
"It's awesome, I don't think I've worked with more connected people in my life."
The Raging Bull icon formed an unlikely friendship with 50 Cent after working together on 2008's Righteous Kill and last year's (12) cop drama Freelancers.