Frank, ready to disown his family, takes Liam under his wing and starts a new life barricaded on the top floor of the Gallagher home. Meanwhile, Fiona starts running Patsy's Pies on her own terms; Debbie gets into trouble in the stroller business; Ian tries out heterosexuality; and Carl finds himself forced into abstinence.
Fiona informs Chad, the owner of Patsy's over her desire to resign from her job and returning as a waitress, however she is informed about the restaurant's financial state and recommends her to hire her own staff; she fires the current waitresses and hires three young women including one who introduces her to dating via social media.
Frank has recovered as Kev is happy to see this while the Gallaghers insult him. Frank disowns his children who are more than pleased by this and kick him out but Frank takes his only loyal child Liam. Ignoring Lip and Ian's protests, he leaves with his youngest child while Kev remarks Frank may be a good father to Liam as they doubt this. Frank confronts Debbie by stealing her card and tells her of his disowning decision as she begins using her daughter's middle name to distance her child from Frank. Debbie warns Liam of their father's ways and says he is in for disappointment like she was.
Using Debbie's stolen credit card, Frank gets revenge on his family by hiring demolition workers to help construct walls around the Gallagher house leaving the rest of the family scattered by sleeping in the living room. The family already deduce this was Frank's way of getting back at them and are angry with his actions.
Frank takes Liam to the Alibi and gets a new girlfriend before he barricades himself in the upstairs while his children try to get rid of him. Frank also tortures them by throwing a raccoon downstairs, as a further way of getting revenge.
Kev becomes quite comfortable with his polygamous relationship, however when left the task of cleaning the house and shenanigans with the kids, he ends up being scolded by V and Svetlana; the failed job of a 'maid' inspires Kev with the idea of a real topless maid service to the women. Ian avoids Caleb and questions his actions and sexuality including his own. Lip starts a new job as a intern while continuing to deal with his alcohol problems. Debbie fully starts a toddler merchandise scam.
Carl continues to struggle with erectile dysfunction. His brothers feel guilt over teasing him and get him painkillers to ease his pain
At the end, the Gallaghers demolish walls in their house while Frank and his girlfriend flee the house after they get upstairs.
- William H. Macy - Frank Gallagher
- Emmy Rossum - Fiona Gallagher
- Cameron Monaghan - Ian Gallagher
- Jeremy Allen White - Phillip Gallagher
- Ethan Cutkosky - Carl Gallagher
- Emma Kenney - Debbie Gallagher
- Shanola Hampton - Veronica Fisher
- Steve Howey - Kevin Ball
- Isidora Goreshter - Svetlana Yevgenivna
- Frank is back on his feet after getting out the wheelchair.
- Frank disowns his children except Liam and gets revenge on them for trying to kill him by blocking them out the rooms of the house and dropping a raccoon to torture them.
- Debbie references Season 3 when she tells Liam of how she discovered their father was a deadbeat.
- Kev appears to notice Frank can be a good father, when he tries.
- Debbie renames her child to distance her from Frank.
- This is the final appearance of Caleb.
- Ian has sex with a woman for the first time.