Mistresses season 3 prefinale: Joss and Calista fight in prison as producer teases Marc and April's romance

Mistresses season 3 returns with its penultimate episode on 27 August on ABC. Episode 12 is titled, Reasonable Doubt, where Joss, April and Karen will be forced to question their choices.

The official synopsis of episode 12 reads: "Despondent over her situation, Joss struggles with whether she should take a plea deal and what that would mean for a future with Harry. Karen agrees to help Vivian keep her secret from Alec so that he can accept a very important award."

Moreover, April and Marc are blind-sided by a surprise visit from Marc's sister Miranda. After being shut out by Joss in prison, Calista sees the pain she's causing her and makes her next move.

Click here to watch it via live stream on ABC Go, or you can watch it online here.

Joss was arrested for the murder of Luca, after Calista (Jennifer Esposito) fed the cops "incriminating details", but it also made her a prime suspect in the case. In episode 11, Joss' lawyer revealed that although Calista is now a suspect in the death of her husband, Joss is being considered a co-conspirator.

A new promo of the upcoming episode shows, Joss confronting Calista in prison as the couple are involved in a typical prison fight.

Meanwhile, executive producer KJ Steinberg has teased Marc and April's future and said, that will be the biggest risk to the couple's potential romance.

Steinberg told TVLine, The secret lapse would definitely be more of a threat, hinting at the fact that Marc never told April about his alcohol relapse or the fact that his sister was the woman for whom April's first husband feigned his death to start a new life in Florida.

"Miranda, you know, isn't really family [to April], so that hasn't been an issue for either of them," he said and added, "Marc's battle with the bottle, however, will play into the final two installments of Season 3."