'Mistresses' season 4 spoilers: Joss testifies against Wilson in murder trial; still dealing with traumatic past

Season 4 of "Mistresses" finally returns next Monday to provide a resolution to last season's cliffhanger finale.
Season 3's thrilling finale saw Joss finally gaining her freedom. While she was all ready to join beau Harry in Europe, she decided to stop by Calista's place to determine what really happened to her. She discovered that she was not alone and that the dangerous Wilson was there pointing a loaded gun at her.
Season 4's premiere episode titled "The New Girl" will pick up one year after the events of the season 3 finale. Viewers will see Joss in court testifying against Wilson during his murder trial. Although Joss claims to have coped with the traumatic experience, her friends will easily notice she isn't doing too well. It seems that Joss will be using a secret way to cope with the terrifying ordeal she experienced. However, some of the wounds will eventually seep through as she begins to take the next step with her relationship with Harry.
Meanwhile, Marc and April have moved in together and seem to be in the honeymoon phase of their relationship. However, the two also have their own issues as Marc still hasn't found a steady job and April will be preoccupied with the notion that Lucy is growing up too fast.
Also in the episode, Karen tries to cope with motherhood by hiring a male nanny. Jerry O'Connell guest stars as Robert — an aspiring actor/"manny" who will provide much-needed support for Karen. Hilarious hijinks are expected to ensue as Robert makes an unwarranted advance at his beautiful boss.
Unfortunately, viewers may not see what happens to Calista, who was last seen contemplating suicide in her prison cell. This is because actress Jennifer Esposito has decided not to return for another season.
Season 4 of "Mistresses" premieres on May 30, Monday, at 10 p.m. ET on ABC.