Diane Lockhart is about to learn how much nothing she knows. Rose Leslie, of “Game of Thrones” and “Downton Abbey” fame, has just been cast as the goddaughter of Christine Baranski’s high-powered lawyer in CBS’ “The Good Wife” spinoff, Variety has learned.

Leslie plays Maia, a young lawyer who has just joined Diane’s firm after passing the bar. The series begins a year after the events of the finale of “The Good Wife,” with Maia suffering from the crippling aftereffects of being a victim of a financial scam. Said scam, incidentally, also wiped out Diane’s savings and led to her leaving the firm she started (Lockhart & Lee).

Not ones to dwell on tragedy, Diane and Maia join forces with Lucca Quinn (Cush Jumbo) at another one of Chicago’s high-profile law firms. Fan favorite Sarah Steele, who played schemer Eli Gold’s daughter Marissa in “The Good Wife,” is also part of the spinoff’s main cast—Marissa will find she has some previously unused investigative prowess that will come in handy at the firm.

“We’re thrilled to have Rose on board,” said executive producers Robert and Michelle King. “We needed a young actress who could hold her own with Christine Baranski and Cush Jumbo, and Rose is perfect. She’s real, she’s strong and she can play comedy. If we designed an actress from the ground up, we couldn’t have done better.”

The series will be available only on CBS All Access, the Eye’s over-the-top video subscription service, and is set to premiere in February 2017. CBS has been beefing up its slate of All Access exclusives: All Access is currently the home of a new “Big Brother” season, and will have a brand-new “Star Trek” series (helmed by Bryan Fuller) premiering in May 2017.