CBS has officially greenlit Young Sheldon, a spin-off of the megahit sitcom The Big Bang Theory about breakout character Sheldon Cooper's (Jim Parsons) childhood, for the 2017-18 season, the network announced Monday.

Iron Man director Jon Favreau will executive-produce and direct the first episode. Jim Parsons will narrate, Wonder Years-style, as grown-up Sheldon. Unlike The Big Bang Theory, Young Sheldon will be a single-camera sitcom without a laugh track.

As previously reported, 9-year-old Iain Armitage will play the boy genius, and Zoe Perry will play his mother Mary. Perry is the real-life daughter of Laurie Metcalf, who plays Mary on The Big Bang Theory.

Iain Armitage, Jim ParsonsIain Armitage, Jim Parsons

Lance Barber, Raegan Revord and Montana Jordan were also announced as series regulars. Barber will play Sheldon's good ol' boy father. He's best known for playing despicable characters like Paulie G. on The Comeback and Bill Ponderosa on It's Always Sunny in Philadelphia. Revord and Jordan will play his twin sister and older brother, respectively.

A two-season renewal of The Big Bang Theory is imminent.

The series is executive-produced by Chuck Lorre, Steven Molaro, Jim Parsons and Todd Spiewak.

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