(This nonsense goes on for a while; they are the two most worthless people in the entire universe; they were created just to piss you off.)
Everybody at Fiona's is feeling wiggly and excited about movie night. Carl makes some weird-little-kid joke about Fiona and Steve reproducing during the movie, and Fiona awesomely just does this gross, like, Mayonnaise Man voice all billions and billions of sperrrrrm and they finally all settle in. And Steve does show up, and Lip did get his tickets, and they are giggling about their old crummy microwave and how Steve should or shouldn't buy them a new one, as is his wont. Everything feels normal, and safe. For one second.
Debbie shows up, looking like the ghost of a total stranger, and Lip and Ian immediately tag-team in on that, trying to cheer her up, assuming that Frank's done something terrible to her, and she just yells, "Why do you always blame Dad first?" They're honestly confused, because who else is there?
"She's over at Sheila's," Debbie chokes out. "Monica."
Somehow this connects up in Debbie's head with Fiona leaving her behind too, going to the new house with Steve-Jimmy, and she runs off sobbing because she's already carrying so many of their secrets; Steve's just like, "Surprise?" Ian says fuck it and takes off for work, shaken more than we've ever seen him.
Liam keeps screaming "Mommy!" but nobody knows who he means.
Ian shows up at Mickey's house in tears, but Mickey's dad is throwing a fit inside and he's supposed to be at work anyway. Mickey looks at him for a while, not entirely hatefully this time, before agreeing to come to the Kash & Grab in a few minutes.
Monica and Frank go into this Ultimate Martyrdom Tournament where each of the discounts their own violent behavior while trying to score points on the other's violent behavior. Eventually, as things get steamier and scarier, Bob steps in to pull them apart. Sheila inserts herself in turn and Bob bristles -- "Bob. Only Moni call me Roberta" -- and it's obnoxious, and Sheila wonders if they shouldn't just leave Monica alone for a few minutes, to apologize. And to whom?