The problems just continue to pile up in "Madam Secretary" season 4.

The fifth episode, titled "Persona Non Grata," foreshadows more pressing global matters as Elizabeth (Tea Leoni) will be steadfast in proceeding with a conference in Kyrgyzstan that deals with human trafficking. This is despite the inappropriate behavior by a U.S. ambassador.

Elsewhere, Elizabeth and Henry (Tim Daly) begin to worry when their daughter Alison (Katherine Herzer) keeps coming home from her campus.

Meanwhile, the abrupt departure of Bebe Neuwirth's character, Nadine Tolliver, has left a gaping hole in the secretary of state's team. Thankfully, here to step in is Sara Ramirez.

According to Deadline, Ramirez will be joining the cast of the CBS political drama as a series regular. She will be playing the character of Kat Sandoval, a bright political strategist who has made a name for herself on The Hill for her brilliance and for disappearing suddenly — until Elizabeth tracks her down and convinces her to return to the political arena.

CBS revealed that Ramirez's character will be making her first appearance in the show's Nov. 19 episode.

Barbara Hall, creator and executive producer of "Madam Secretary" said, "We're very excited that Sara is joining the cast." She added that the actress brings a new perspective as well as a fun and energetic aura not just to the show but to her character's workplace as well.

Co-executive producer Lori McCreary also expressed excitement about having Ramirez. McCreary added that it was an instant connection as soon as Ramirez walked in on the set, bringing her talent and spirit with her.

This will be Ramirez's first regular TV role after working on the hit ABC medical drama "Grey's Anatomy" which she departed from last year. She played the role of Dr. Callie Torres for more than 10 seasons.

"Madam Secretary" airs every Sunday at 10:30 p.m. EDT on CBS.