What Jada Pinkett Smith Told Will Smith About Working With Margot Robbie

— -- Many wives would feel threatened if they learned that their husband had to get steamy on camera with a hot woman 20 years younger, but not Jada Pinkett Smith.

Will Smith revealed what his wife said when she learned that "The Wolf of Wall Street" star Margot Robbie, 24, was going to be his co-star in the new film "Focus."

"When Margot got hired for the gig ... [Jada] saw that Margot was young and hot and in shape, and she said, 'Boy don't embarrass me. Get in shape now,'" Smith recalled to E! News, with a laugh. "She was like, 'Do not let that girl smash you onscreen.'"

On a more serious note, Smith, 46, explained the secret to his successful marriage to Pinkett Smith, 43.

"We had to shift the paradigm of the relationship -- and we did, with our children and with our family," he explained to E! "There's one relationship to have with people, and that's friendship. So that's a relationship in which you want what is best for them at all times and you're willing to suffer for them to have the thing that is in their best interests."

Recently, Pinkett Smith shared with Shape magazine how she keeps things hot with her husband of 18 years.

"It’s a big turn-on for me to be spiritually and intellectually challenged by Will. To me, it’s like foreplay!" Pinkett Smith revealed to Shape. "Of course, I enjoy that I have sex in my relationship, but I think this other intellectual aspect is quite unique and something that strongly connects us."