Just when we thought “Mistresses” couldn’t get any hotter, everybody’s favorite summer series found a way to steam up the small screen even more. According to reports, fans of ABC’s hit show should prepare themselves for some sizzling-hot drama to go down in episode 4. So, grab yourself a chilled glass of wine -- maybe two -- before Season 3 continues with more searing scenes.

So, what exactly will leave viewers wide-eyed and slightly sweaty during the installment set to be shown Thursday, July 2? Well, the promotional video for episode 4 teases a lot of lip-locking will occur. And, as the wise R. Kelly once said, there’s nothing wrong with a little bump and grind, especially when it involves our beloved mistresses.

“When chemical attractions just can’t be denied, you need a new formula for love,” the episode 4 trailer kicks off with scenes of April (Rochelle Aytes) getting introduced to a handsome hunk, who leaves her unable to speak in full sentences.   

But that’s just the tip of this sexy iceberg. The promo video then teases that the “new formula” being explored will involve Karen (Yunjin Kim) partaking in a ménage à trois come episode 4, with Dr. Alec Adams (Ed Quinn) and his wife, Vivian (Sonja Bennett). But how does this love triangle even begin? Well, in episode 3, Karen began growing close to Dr. Adams -- so close that she felt guilty, finding the need to confess to Alec’s dying wife (to whom Karen was donating stem cells) that she and her husband were not having an affair.

The next thing viewers see is Vivian grabbing Karen by the face and kissing her, passionately, as Alec watches. Just as Karen is about to leave with her lips still tingling, Vivian pleads with Karen not to go.

“But every experiment has its risks,” the trailer warns. Could this threesome be disastrous? After all, there are stem cells on the line.

The synopsis for the episode titled “Into the Woods” then reveals that April will wind up “learning a lesson during Lucy’s [Corinne Massiah] school camping trip” while series newcomer Calista Raines (Jennifer Esposito) “lets her guard down.”

“Mistresses” episode 4, “Into the Woods,” will be shown on ABC Thursday, July 2, at 9 p.m. EDT.