Efron agreed that to play this type of mega movie star, you must be "in on the joke." One line for his character: "My eyes are too pretty not to be seen."
"Yeah, that one was hard to get out," laughed Efron. "You got to bite your lip and go for it--not blink!"
In the film, King's character wants to be a film producer, not just an assistant. The film offers plenty of laugh out loud moments.
"You don't realize how exhausting some of the emotions and the physical comedy in the effort can be because you're just having so much fun doing it," said King. "It's only when you go home at the end of the day that you're, like, 'Whew! What a day! Oh my gosh!' But that feeling is very welcomed. It's a very fulfilling feeling."
Both actors' last projects were dramatic ones. King starred in Hulu's holocaust series, "We Were the Lucky Ones." And Efron was in the wrestling film, "The Iron Claw."
"I can't tell you how refreshing and, like, necessary it is to go to the same creative space. But also, just have fun all day," said Efron. "It kind of reminds you, like, the joy that brought you here--that drove me here in the first place."
Besides working with King, Efron was happy to reunite with Kidman after starring together in 2012's "The Paperboy."
"I'm grateful that she's so trusting in me," said Efron. "She's so brilliant to work with."
"A Family Affair" hits Netflix on Friday, June 28.