In Fire Country season 4, episode 7, titled “Best Mom in the World,” viewers will finally get to see Sharon’s mother, Ruby, played by Oscar-winning Christine Lahti. The sudden and unexpected arrival of an estranged family member will catch Sharon off guard. The Cal Fire leader will be forced to dredge up painful memories from her past. The episode airs on Friday, December 5 at 9 p.m. ET.

First-look images of Lahti as Ruby have been revealed by CBS. In the first image, Ruby wears a serious expression on her face while holding a rag inside Smokey’s Tavern.

The second image also takes place inside the bar, with Sharon sitting down as she looks up at her mother, who has her arms folded across her body. Both of them appear to be in the middle of a serious conversation, likely tied to the painful memories that Sharon will have to confront in this episode. Take a look at the images below:

Elsewhere in the episode, Sharon’s son, Body, and Jake are on the job as they help a troubled teenager inside a condemned building. Lahti won an Oscar for directing the short film Lieberman in Love and was nominated for her acting role in Swing Shift.

On the small screen, she’s appeared in several shows over the years, including Frasier, Ally McBeal, Studio 60 on the Sunset Strip, Law & Order: Special Victims Unit, Hawaii Five-0, Grace and Frankie, The Blacklist, The Good Wife, and Curb Your Enthusiasm.

Vince and Body are not Sharon’s only family members who have appeared on Fire Country. Morena Baccarin guest-starred in two episodes as Sharon’s step-sister, Mickey Fox, and W. Earl Brown made an appearance as Wes Fox, her step-father.

Both actors now star in the Fire Country spinoff Sheriff Country, which follows Mickey as the sheriff of Edgewater as she deals with the criminal activity in town, as well as the headaches caused by her father and daughter, Skye, played by Amanda Arcuri. A few Fire Country characters, including Sharon and Bode, guest-starred in early episodes of Sheriff Country, which debuted in mid-October.

Sharon is no stranger to dealing with family drama, which will worsen with the arrival of her mother, Ruby, in an upcoming episode of Fire Country. She’s still mourning the loss of Vince after the events of the Fire Country season 3 finale, so Ruby’s visit will likely only make the situation worse and cause Sharon’s stress and anxiety to escalate. Hopefully, they’ll manage to depart on better terms than when the episode starts.

Fire Country airs Fridays at 9 p.m. ET on CBS.