Things are really starting to heat up on Season 3 of “Mistresses.” But hey, what else did you expect from the summer’s hottest series?

Although episode 4 of the ABC installment featured a few eye-widening moments, which we’ll get to in a moment, “Into the Woods” kicked off on an emotional note as Joss (Jes Macallan) and Harry (Brett Tucker) discussed the future of their relationship.

“Never in a million years, from where we started, did I think we’d end up here,” the grinning Aussie says to his beau while in bed, prompting her to ask: “And where would you say we were?”

“Happy,” he replies. But his response leaves Joss feeling anything but content. She was looking for an answer that would help define their relationship, not a jovial adjective.

Joss reveals her frustration over Harry’s response to her friends. She’s convinced that the man she lost her sister (Alyssa Milano) over is having doubts about their relationship. But April (Rochelle Aytes) and Karen (Yunjin Kim) speculate that Harry is probably just weary of labels or nervous to dive head first into another relationship.

Joss decides to prove to Harry he shouldn’t be timid of starting a relationship with her by accompanying the chef on his house-hunting mission. That's when the two decide that maybe it’s time they move in together. After all, they have been dancing around this relationship for over a year. But when Harry turns his nose up as Joss’ well-priced, and well-located dream pad, she begins to become doubtful about their relationship once again.

Joss’ insecurities flare up later on that night when she pays Harry a visit at work with another potential home. But Harry says he’s just too busy to even take a peak at the house. That’s when a fight ensues. However, shortly after their argument, Harry tries to amend things with the love of his life through a text that says, “Hey, we should talk.” Joss sees it and replies back with an apology. But the pesky bartender Niko (Emmanuelle Vaugier) deletes Joss' message.

And it looks like Joss isn’t the only one having relationship issues. In episode 4, Calista (Jennifer Esposito) and Luca (Noam Jenkins) prove why they’re relationship has been on the rocks for the past decade as fans watch their on-again, off-again romance unfold in under ten minutes. Calista, who has been convinced that her husband has been cheating on her since she made her debut in the Season 3 premiere, accompanies her alleged disloyal beau for dinner in celebration of their ten-year anniversary. However, the romantic outing takes a turn for the terrible when Luca presents Calista with a sparkling gift -- a dazzling necklace that he designed for his potential, forthcoming line “Accessories by Luca,” which he wants to sell under Calista’s brand.

That’s when she realizes that the dinner isn’t about honoring their anniversary but strictly about business. “You’re a selfish b------. Do not follow me home,” she warns. But he does. And soon their heated arguing turns into steamy makeup sex.

Speaking of which, Karen finds herself smack in the middle of an Adams sandwich when Vivian (Sonja Bennett) and (Ed Quinn) ask her to join them in a ménage à trois. See, Vivian has been feeling undesirable since she was first diagnosed. Her husband has been treating her more like a patient than a lover, causing their sex-life to fizzle away. But Karen suggests something to her friend that could possibly put the sizzle back in their sex life: a sexy makeover. The two ladies get dolled up as they puff away on Vivian’s medical marijuana. But just as they apply stains to their lips, they duo partake in a serious heart-to-heart.

“You’re afraid you’re attracted to my husband. You’re pushing us together so you don’t pull us apart,” Vivian says to Karen, who then confesses that yes, she does find Dr. Alec easy on the eyes. But according to Vivian, she finds something oddly sexy about her friend thinking her husband is hot.

That’s when Alec suddenly walks in. But instead of him noticing his wife’s makeover, he’s only concerned about her health -- and the overwhelming smell of marijuana. To get her husband to really see her, Vivian kisses Karen. She then walks over to Alec and lays one on him.

As the couple locks lips, Karen begins to make her exit. Her job is done after all, right? Just then, Vivian grabs her by the arm.

“Karen, don’t go,” she says. “Please.”

While Karen struggles whether or not to partake in TV’s hottest three-way, April finds herself coming face-to-face with a problem herself: her daughter.

According to Lucy’s (Corinne Massiah) headmaster (Brian White), Lucy's grades are dropping so low that she could lose her scholarship. After explaining that her daughter is having difficulties since losing her father -- again, Blair suggests that maybe Lucy pack her bags for the school’s camping trip to help find herself again. But the only thing Lucy finds in the middle of the woods is a whole lot of trouble when she gets caught smoking in the trees. (Um, can you say forest fire?)

Thanks to some parental advice from Blair (who is also a single parent since losing his wife five years ago), April manages to earn respect from her daughter after scolding her rebellious pre-teen in public instead of trying to act like her friend.

What did you think of episode 4 of “Mistresses”? Sound off in the comments section below and don’t forget to tune in to the ABC series on Thursdays at 9 p.m. EDT.