Brilliant 7-year-old Madeline "Matty" Matlock, after achieving success as a younger woman, decides to return to the working world of a prestigious law firm, where she uses her unassuming demeanor and cunning tactics to win cases and expose corruption from within. Matty is assigned to Olympia, an older attorney and rainmaker with a thirst for justice, while Olympia's ex-husband Julian, the son of the firm's president, takes an interest in Matty and his smarts. Matty works with the firm's younger partners - the charismatic Billy and the extremely ambitious Sarah - as she tries to establish herself in this new high-stakes world.