Things are getting pretty dark on Season 3 of “Mistresses.” Not only did viewers witnesses a gruesome murder take place in episode 7 of the ABC series, but they’ve also watched countless relationships fall apart throughout the third installment – like the romance between Karen (Yunjin Kim), Alec (Ed Quinn) and Vivian (Sonja Bennett).

In the previous episode, audiences saw Karen and Alec’s passion for one another bloom while Vivian was out of town. However, the duo both felt a bit guilty that they had slept together without their third partner, so, they decided to keep their weekend rendezvous under wraps.

But according to the synopsis for episode 8, titled "Murder She Wrote," their plan to keep their love affair low key won’t pan out. And eventually Vivian will discover both her partners have been lying to her, which will led to the demise of everyone’s favorite love triangle.

Meanwhile, Marc (Roby Mayes) will confront his own demons, the summary reveals, after he endures a “series of blows to his self-esteem.” Could one of those blows be losing April (Rochelle Aytes) to Blair (Brian White)? Viewers saw that Marc had grown feelings for April, but Lucy’s (Corinne Massiah) mother is clueless to the fact that the man living in her home has a crush on her. Perhaps April will see the light when Blair unleashes his “very strict side,” the synopsis adds.

But the most grim aspect of episode 8 involves the demise of Luca (Noam Jenkins). In the earlier installment, Joss (Jes Macallan) concocted a wild plan with Calista (Jennifer Esposito), hoping to catch the designer’s husband cheating on her. Calista explained that her finances depended on it – if she was to divorce Luca without proof he was unfaithful, he would take half her earnings.

So, Joss, being the good friend she is, decided to play a lead role in Calista’s plan of revenge, portraying a seductive mistress. The faux affair between Joss and Luca was then caught on tape, however, a power outage put a damper on the night. As Joss tiptoed down Calista’s enormous staircase looking to flee, she tripped and fell… over Luca’s dead body.

The synopsis states that Calista will throw Joss “under the bus with the police” in episode 8, which ultimately causes Joss to become the main suspect in the case of Luca’s murder. Guess Calista isn't the friend Joss thought she was.

Who do you think killed Luca? Sound off in the comments section below before “Mistresses” airs Season 3, episode 8 on Thursday at 9 p.m. EDT on ABC.