A violent meth dealer threatens the Gallaghers, forcing Ian, Carl, Lip and Debbie to find a way to pay him off without involving Fiona. Fiona battles it out with a vindictive tenant. Lip cares for a down-and-out Professor Youens. Frank - miraculously - attains something resembling sainthood.

A blast from the past shakes up Fiona's view of her life. Frank gets involved with Liam's school and becomes the most popular dad in the PTA. Lip learns getting laid is harder than anticipated when sober. Ian crosses a boundary with a kid from the youth center. Kev and V take a trip to meet his birth family.