"People thought I was crazy," Henson, 44, tells PEOPLE of deciding to leave her lucrative job back home in Washington, D.C. to take a shot at making it big in Hollywood.
Henson had graduated from Howard University and was working as a supervisor on a five-star dining cruise when she packed up her son Marcel, now 20, and moved to California at the age of 26.
"My dad knew that acting was my calling," says Henson. "One day, he looked at me and said, 'How do you expect to catch fish on dry land?' So I moved out here with my son with $700 in our pocket."
Though she would go on to score a role in the critically acclaimed Hustle & Flow and an Academy Award nomination for playing Brad Pitt's mother in 2008's The Curious Case of Benjamin Button, Henson says she did not find success easily.
"You just have to stay the course and not getting distracted or compare yourself to others," she explains. "You have to really stay focused and stay grounded."
When opportunities did not present themselves, Henson says she went out and made her own by producing theater productions with her friends.
"I wasn't in California to party and go to clubs," she says. "I just kept myself immersed in the craft of acting so that when opportunity struck, I would be ready."
And ready she was.
"I just knew we had something special," Henson says of her first time reading the script for the hit Fox drama, which airs Wednesdays at 9 p.m. "This is what happens when you have great material and a studio that's behind it and ready to take a risk – it was the perfect storm."
With Empire's continuing to gain steam as it leads up to the season finale on March 18 – and a second season already green lit – no one could be prouder of Henson's success than her son.
"He's been with me through this whole process, so he's known my struggle. He's very proud because he knows what I've been working so hard for," Henson says of Marcel. "He's like, 'Mom, you're finally getting what you've always wanted.' "
For more on Henson's raise to fame, pick up the latest issue of PEOPLE, on newsstands Friday