The Captain Marvel star was described as the "ostensible lead," according to The Hollywood Reporter. The previously cast Finn Wolfhard (Stranger Things) will play her brother and Carrie Coon (The Leftovers) will star as her mother.
Reitman confirmed the casting Friday, sharing photos of Coon, Wolfhard and Grace. "Meet the Family," he wrote.
The script was written by Reitman and Gil Kenan, and is expected to focus on four teenagers and one specific family. It was previously reported that the family have some "mysterious ties back to the original 1984 movie." However, more plot details are being kept under wraps.
"I've always thought of myself as the first Ghostbusters fan, when I was a 6-year-old visiting the set. I wanted to make a movie for all the other fans," Reitman said in January. "This is the next chapter in the original franchise. It is not a reboot. What happened in the '80s happened in the '80s, and this is set in the present day."
Grace, 12, starred as a young Theodora Crain in Netflix's The Haunting of Hill House and is one of the busiest young actors in Hollywood today. She played a young Tonya Harding in I, Tonya, had a small role in Ready Player One and starred as the young Carol Danvers in Marvel Studios' Captain Marvel.
Her next film is Troop Zero, a coming-of-age movie about elementary school girls who are joined by a youth group to win a talent show. It debuted at the Sundance Film Festival in February and was acquired by Amazon. On June 28, she will be seen in the next Annabelle movie, Annabelle Comes Home.
Grace also has a recurring role in Netflix's Fuller House as Rose Harbenberger and in CBS' Young Sheldon as Paige. She also played a young Sabrina Spellman in Netflix's Chilling Adventures of Sabrina.
Back in January, Sony surprisingly announced that Reitman was working on a new Ghostbusters movie that would serve as a follow-up to 1984's Ghostbusters and 1989's Ghostbusters II, which were directed by his father, Ivan Reitman. It will not take place in the same universe as the 2016 Ghostbusters, which featured an all-female group of Ghostbusters.
The original Ghostbusters starred Dan Aykroyd, Bill Murray, Ernie Hudson and the late Harold Ramis. It's not clear how involved Aykroyd, Murray and Hudson will be. Hudson has expressed interest in returning though.
Ghostbuster 3, which has been in production under the code name Rust City, will hit theaters on July 10, 2020.
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