Meanwhile, CBS has yet to confirm that the project has been picked up to pilot.

CBS' Big Bang Theory prequel, Sheldon, is moving forward — despite not having an official pilot order.

After an extensive casting search, the half-hour comedy has found its young Dr. Sheldon Cooper in Big Little Lies actor Iain Armitage, as well as Sheldon's young mother with Zoe Perry (Scandal) set to play Mary Cooper, The Hollywood Reporter has learned. CBS and producers Warner Bros. Television declined comment.

Sheldon will be written by Big Bang co-creator Chuck Lorre and showrunner Steve Molaro, with fellow co-creator Bill Prady also said to be on board. The comedy will center around the young version of Emmy winner Jim Parsons' Sheldon. The comedy has been described as Malcolm in the Middle but with a young version of Sheldon. None of the Big Bang Theory cast will be involved in an onscreen role, but Parsons is on board as an executive producer.

Unlike the multicamera Big Bang — TV's No. 1 scripted comedy in the all-important adults 18-49 demo — Sheldon will be a single-camera comedy. The project, from Warner Bros. Television — where Lorre and Molaro are under rich overall deals — is said to have landed at CBS with a sizable penalty attached.

During Big Bang's 10-season run, many references have been made to Sheldon's childhood, growing up as a gifted youngster in Texas with a religious mother. Perry is the daughter of Scandal star Jeff Perry and his ex-wife, Laurie Metcalf, the latter of whom has recurred throughout the show's 10-year run as Mary Cooper, Sheldon's mom. A prequel series would also give the writers a lot of material to work with given Sheldon's history, as well as a structure to follow. Big Bang, unlike most series on TV, does not plot out its arcs and seasons ahead of time — the writers take it episode by episode.

The Sheldon pilot pickup comes as the pricey contracts for the seven lead stars of Big Bang expire at the end of its current 10th season. A new two-year deal is said to be in the works, as new deals with the cast are being drafted.

For his part, Armitage will next be seen playing Shailene Woodley's son in HBO's Big Little Lies adaptation. On the feature side, he has three movies due this year: J.K. Simmons' I'm Not Here, Robert Redford's Our Souls at Night and Brie Larson's The Glass Castle. Armitage is repped by Abrams Artists and Jackoway Tyerman.

Perry, meanwhile, is recurring this season opposite her father on Scandal and counts Grey's Anatomy (as a patient) and Private Practice as well as a role opposite Metcalf on Roseanne, The Family and ABC's Conviction among her credits. She is repped by AKA.

Sheldon is one of multiple spinoffs in the works this season. ABC is also prepping a 1990s-set spinoff of The Goldbergs as well as a college-focused offshoot of Black-ish, starring Yara Shahidi. In an era of dwindling mass-audience TV hits, spinoffs are seen as a proven way to keep bankable franchises going. CBS is also looking to The Good Wife for its All Access spinoff, The Good Fight, and NBC is poised to launch an offshoot of The Blacklist with The Blacklist: Redemption, which will join its deep roster of Dick Wolf's Chicago spinoffs.

Should Sheldon move to series, it would be Lorre's second show on broadcast (joining CBS' critical favorite Mom) and third overall (joining Netflix's Kathy Bates pot comedy Disjointed).

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