The arrival of a movie star turns ``Bombshell'' upside-down; Ivy and Karen try to overcome their history and unite against their new rival; Tom and Sam's romance heats up.

Karen finds herself seduced by the glamorous life of new BFF Rebecca Duvall -- but can Rebecca be trusted? What will Karen's ascent mean to her relationship with Dev? And will Rebecca drive Derek insane? Eileen introduces new beau Nick to ex-husband Jerry, while Julia panics when her son Leo goes missing.

As Tom and Julia race to ready "Bombshell" for previews, Tom's eagerness to prove himself may not be the best thing for the show. An on-stage mishap forces Ivy to make an important decision, while tension rises at "Hit List" as Karen becomes suspicious of Derek's motives towards her.

It's "Bombshell's" opening night. As Ivy's nerves get the better of her, support comes from an unlikely source. Meanwhile, Tom and Julia look to their next project. "Bombshell's" success may be in jeopardy as Eileen's issues with Richard come to a head. Jimmy finally opens up to Karen about his past, but is it too little too late?