The legal thriller, first published in 1991, focuses on Mitchell Y. McDeere, an ambitious student who unwittingly becomes involved with a corrupt law firm.
According to Entertainment Weekly, NBC is considering a full 22-episode season order for the project, with Grisham on board as executive producer and Law & Order's Luke Reiter attached as showrunner.
eOne Television will serve as the primary production company and will sell the show to foreign markets.
The Firm previously served as the inspiration for a 1993 film, which starred Tom Cruise as McDeere. A television adaptation of the novel was previously in development at CBS.
Other projects currently in development at NBC include a Wonder Woman pilot, period drama Reconstruction, the controversial The Playboy Club and a new comedy starring Christopher Lloyd..
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