Wayans, who is usually seen in comedy roles, plays Aretha's first husband Ted White in the new biopic, and he admits he was so mesmerized by his castmate he would do anything for her, almost serving as her personal assistant.
"This girl was working hard," he raves. "She was singing everything live take after take after take. Her instrument is so strong, she never even asked for hot lemon and water. The woman is a machine."
"I just made sure as her co-star, if she needed anything... I would be there for her. I'd be like, 'Do you need water? Do you need food? Girl, it's been five hours; eat something...' She did a lot of dance numbers and I'd get her a massage. I took care of her and that built a great onscreen chemistry."
And Wayans has become the ultimate Hudson pitch man, insisting she was an absolute joy to work with. "I want people to see this movie just to see her performance," he adds. "It's literally a work of genius."
He also enjoyed working with Forest Whitaker, who plays Aretha's father in the film.
"He's amazing," he gushes. "I improvise with comedy; this man improvises with drama and he went there. We did a scene and he tried to evoke emotion and he wanted fear to be the emotion. Forest pulled out a gun and we're all like, 'Oh, that's not in the script...!' 30 takes and it worked every time."