Who killed Luca (Noam Jenkins)? That’s the question on every fans mind -- and in episode 9 of “Mistresses,” titled “Unreliable Witness,” viewers of the hit ABC series got one step closer to finding out who was responsible for the death of Calista’s (Jennifer Esposito) husband.

The Season 3 installment kicks off with Karen (Yunjin Kim) weeding out incompetent lawyers in an attempt to find the perfect one for Joss (Jes Macallan), who is a suspect in the case of Luca’s murder. But finding a textbook attorney is just one of Karen’s issues -- she also needs to figure out a way to keep Joss from blabbing away about ridiculous Calista theories ... like how Calista spotted her out of the crowd (because she looked like an easy target) to pin Luca’s murder on.

Despite the odds working against Joss, Karen promises her friend that she’ll be with her “every step of the way.”

Meanwhile, Marc (Rob Mayes) faces his inner demons in episode 9 as he was forced to confront his alcoholism. But before Marc could get better he got worse – a lot worse. The bartender wakes up next to an empty bottle of liquor and not to mention … completely hungover. But Marc manages to pick himself up to get his paycheck.

When Marc gets to work, he bumps into Harry (Brett Tucker) who begs for his assistance. (A new mixologist was just hired and he was doing a terrible job). However, Marc declines -- leaving Harry alone with the insufferable newbie.

Although the new hire couldn’t manage to make a tequila sunrise, the social media-obsessed employee did inform Harry that Joss’ friend Calista had just become a widow. The news about Luca’s death causes Harry to immediately want to seek out Joss.

While Harry tries to get in touch with Joss, Karen eventually finds a sharp lawyer to represent her friend -- and luckily for Joss (and audiences), he was pretty easy on the eyes! Right after finding an attorney capable enough to help Joss out of the jam she wiggled her way into, Harry barges into Karen’s home.

“Harry, I can’t do this with you right now,” Joss says to her former beau, revealing that she has enough things on her plate like being accused of murder. “And you slept with Niko [Emmanuelle Vaugier].”

Karen tells Harry that he needs to give Joss space. Otherwise, her life will only become more complicated and chaotic. So, the cook (reluctantly) agrees. And thank goodness he does because Harry had his hands full with his own issues when Marc shows up to work drunk the following day.

The cook kicks Marc out of the restaurant but later finds his bud in his home, completely intoxicated. That’s when Marc reveals to the Aussie hunk that he’s a recovering alcoholic – or at least … he was until Harry gave him a beer.

“I want to help,” Harry says, revealing that his dad was also an alcoholic. That’s when Harry asks his friend to call his sponsor, which he does. But we have a feeling there’s something more between their relationship that Marc isn’t letting us in on.

But the issues don’t stop there. In episode 9, the manipulative fashion designer sends Joss a bouquet of flowers. “I love you. Were going to get through this together,” the note reads. But Joss isn’t impressed by Calista’s kind words. Instead she throws the bouquet across the room in a  fit of rage. How could someone be pinning a murder on you one second then sending you a gift the next?

Karen, however, isn’t interested in finding out the answer to that question. Instead, she heads over to Calista’s house to tell her to leave Joss alone. But Calista swears she and Joss are buddies

“You don’t sell [friends] down the river when things aren’t going your way,” Karen barks back, before warning Calista not to make her come back to her house.

But Karen shouldn’t worry about Calista messing with Joss’ emotions anymore. Following Joss’ flub during her interrogation (she said she was never in Calista’s basement but they found her fingerprints on the doorknob), the brilliant party planner put her organizational skills to work as she dug up dirt on her seemingly clean foe.

Remembering that Calista used to go by the name of Carla, Joss learned that the designer’s first husband was also killed in a shooting. Feeling suspicious, Joss paid the mother of Calista’s dead ex a visit.

“My Justin was a sweet boy,” the mother said, revealing that she didn’t believe her son committed suicide like the report said. “Justin, he got in her way.”

Justin’s mom added that she knows Calista had something to do with his death – after all, her son didn’t even own a gun! The weapon used to kill him actually belonged to Calista. So, Joss reveals that interesting bit of intel to her lawyer, who said that perhaps they could use that in their case against Calista.

But when Calista gets wind that Joss is using that personal tidbit against her, she flies off the handle and pays her blabber mouth “friend” a visit. Joss says that she told her lawyer about the death of Calista’s ex because she knows the designer was involved with the murder.

“I don’t think that you did it. I know that you did it,” Joss states.

“Karen was right. We’re not friends. Good luck, kid. You’re going to need it,” Calista threatens. And apparently her threat was anything but empty. Calista goes straight to the police where she reveals to officers that Joss, who is “obsessed” with her, once said that she would kill Luca after she saw him flirting with another woman.

“And now he’s dead. So, you tell me,” she says to the detective.

Moments later, audiences watch as Joss gets thrown into the back of a police car with tears streaming down her cheeks. But the episode didn’t just end with that major moments. Viewers also learn that the reason Karen was feeling so sick throughout the episode was because – she’s pregnant! Or at least, that’s what we assume was the outcome after Karen tossed her wine down the sink. (She would never waste a glass of white unless she was with child, right?)

Lastly, Blair (Brian White) and April’s (Rochelle Aytes) relationship gets even more serious in episode 9 of “Mistresses.” However, April is hit with a bit of a curve ball when her daughter reveals she’s not too fond of the headmaster.

“I don’t like him,” Lucy (Corinne Massiah) says about her mother’s strict boyfriend.

“Mistresses” airs Thursday nights at 9 p.m. EDT on ABC.