Worldstar! is the ninth episode of Season 4 and the 45th overall episode.
Lindsay's mom comes to town, shedding light on the origin of Lindsay's issues, while Jimmy attempts to get over Gretchen by hooking up with someone from his past. Meanwhile, Edgar struggles to reconcile his new writer life with his old veteran life.
Gretchen wakes up next to her phone and realizes she and Jimmy fell asleep together while talking the previous night.
Lindsay sets out to punch Becca as punishment for "ruining her life", with Gretchen ready to capture the moment on video. However Lindsay's mother Faye (Robin Riker) answers the door.
Faye is a B-list actress whom Vernon says appeared nude in some late-night cable movies back in the 1980s.
Becca starts belittling Lindsay about being married to a doctor while Lindsay is divorced, having a child while Lindsay aborted hers, etc.
After Becca's superiority rant, she and the group walk in on Vernon masturbating to one of Faye's old movies. Becca breaks down, calling her husband a "penis in a clown wig" and admitting they are broke.
Jimmy arrives home full of himself and optimistic about Gretchen after the late-night talk, but Edgar tells him about Boone showing up at the divorce party.
Back at Lindsay's apartment, Edgar and Max order food while working on a script. It is delivered by one of Edgar's old Army comrades.
When Edgar says he doesn't like to talk about his days in Iraq, the guy criticizes him and Edgar gets revenge by humiliating the guy for a $50 tip.
Becca, Lindsay, and Gretchen watch some old family videos that indicate Faye neglected her daughters when they were very young.
Jimmy tries to move on from Gretchen by hooking up with Katherine, an old acquaintance from England, but is surprised to find that his formerly plain classmate has become a beautiful and successful attorney.
Katherine looks down on Jimmy and reminds him that he was an outcast in school whom everyone called "Shitty Jimmy".
Gretchen arrives back at the house and sees Jimmy and Katherine having hateful sex.